No, you're not buying a handgun; at least according to the BATF info below. This makes all the other questions moot. Maybe just get a nice big walking stick? Enjoy your trip!

ATF Online - Firearms - Frequently Asked Questions - Unlicensed Persons

Q: May aliens legally in the United States buy firearms?

An alien legally in the U.S. may acquire firearms if he has a State of residence. An alien has a State of residence only if he is residing in that State and has resided in a State continuously for at least 90 days prior to the purchase. An alien acquiring firearms from a licensee is required to prove both his identity, by presenting a government-issued photo identification, and his residency with substantiating documentation showing that he has resided in the State continuously for the 90-day period prior to the purchase. Examples of qualifying documentation to prove residency include: utility bills, lease agreements, credit card statements, and pay stubs from the purchaser’s place of employment, if such documents include residential addresses.See also Item 5, “Sales to Aliens in the United States,” in the General Information section of this publication.[18 U.S.C. 921, 922(b)(3), (d) and (g), 27 CFR 478.11 and 478.99(a)]

Q: Are there certain persons who cannot legally receive or possess firearms and/or ammunition?

Yes, a person who —

1. Has been convicted in any court of a crime punishable by imprisonment for a term exceeding 1 year;
2. Is a fugitive from justice;
3. Is an unlawful user of or addicted to any controlled substance;
4. Has been adjudicated as a mental defective or has been committed to a mental institution;
5. Is an alien illegally or unlawfully in the United States or an alien admitted to the United States under a nonimmigrant visa;
6. Has been discharged from the Armed Forces under dishonorable conditions;
7. Having been a citizen of the United States, has renounced his or her citizenship;
8. Is subject to a court order that restrains the person from harassing, stalking, or threatening an intimate partner or child of such intimate partner; or
9. Has been convicted of a misdemeanor crime of domestic violence
10. Cannot lawfully receive, possess, ship, or transport a firearm.

Excellent......thanks for the answer.
I shall enjoy my trip, meeting people, climbing hills and not getting eaten by bears.
I must admit it is a weight off my mind....I was unsure it was necessary, and now I know I will have to rely on your hospitality and my good sense.
It worked when I went to Alaska, and I can tell my Californian cousin everything's fine......

Originally Posted by Mycroft

Hello everyone,
I will be visiting the US for a holiday in the spring of 2013. I have a relation in California who insists that as I will be travelling around and sightseeing and hill walking I should arm myself. I live in the UK and as you probably know no handguns are allowed over here. For anyone. Ever. At all!
I own a good old fashioned English side-by-side 12 bore that I use for game shooting, and was on my school .22 rifle team in the 1970's.
I have no intention of shooting anyone, it's just that if people think I should be armed......perhaps I should.
I will be flying into Boston, MA and travelling through Vermont, Maine & Massachusetts for three weeks, mostly in a hire car.
Would it be possible for me to buy a handgun? Do I really need one? How much practice and tuition would I need? What calibre? Could I sell it back to a gun store before I return home.........
Lots of question folks as you can see.
Any help, information and advice gratefully received!
Thanks for reading.

Mycroft the Brit.

Although we do have our share of crime, you will not be able to purchase a handgun while you are here. Its not that bad here - unlike CNN would have you to think. Too bad about you guys in Britain not being able to own a handgun anymore. From the research I have done, it did not do a damn thing at all to help slow down crime in your country - this is something us gun owners already know though. Hope you enjoy your stay here.

If you are in bear country make noise and carry a large canister of bear pepper spray. Bears do not like being pepper sprayed any more than people do. As for two legged nasties stay aware of where you are and if the area looks unsavory assume that it is and don't stop/leave that area. And have a Nice vacation.

Q: How do you protect yourself from bears?
A: Wear small bells that make continual noise as you walk, and carry a can of pepper spray for use in case of attack.

Q: How do you know whether bears are in your area?
A: Look on the ground for bear droppings.

Q: How can you tell if they are bear droppings?
A: Bear droppings smell of pepper spray, and contain little bells.

Originally Posted by Steve M1911A1

Q: How do you protect yourself from bears?
A: Wear small bells that make continual noise as you walk, and carry a can of pepper spray for use in case of attack.

Q: How do you know whether bears are in your area?
A: Look on the ground for bear droppings.

Q: How can you tell if they are bear droppings?
A: Bear droppings smell of pepper spray, and contain little bells.

Exactly what I needed to get my day started off into the right direction. Thanks for the laugh!

Originally Posted by Steve M1911A1

Q: How do you protect yourself from bears?
A: Wear small bells that make continual noise as you walk, and carry a can of pepper spray for use in case of attack.

Q: How do you know whether bears are in your area?
A: Look on the ground for bear droppings.

Q: How can you tell if they are bear droppings?
A: Bear droppings smell of pepper spray, and contain little bells.

Can always email Timothy Treadwell and ask him. Oh, wait.... he forgot his bells and pepper spray, didn't he?

Originally Posted by Mycroft

Hello everyone,
I will be visiting the US for a holiday in the spring of 2013. I have a relation in California who insists that as I will be travelling around and sightseeing and hill walking I should arm myself. I live in the UK and as you probably know no handguns are allowed over here. For anyone. Ever. At all!
I own a good old fashioned English side-by-side 12 bore that I use for game shooting, and was on my school .22 rifle team in the 1970's.
I have no intention of shooting anyone, it's just that if people think I should be armed......perhaps I should.
I will be flying into Boston, MA and travelling through Vermont, Maine & Massachusetts for three weeks, mostly in a hire car.
Would it be possible for me to buy a handgun? Do I really need one? How much practice and tuition would I need? What calibre? Could I sell it back to a gun store before I return home.........
Lots of question folks as you can see.
Any help, information and advice gratefully received!
Thanks for reading.

Mycroft the Brit.

Your friend is spouting rubbish. Unless you are going to drink heavily and wander mistakenly into one of our numerous and unlovely ghettos, then you will not need a firearm. Or, at least the odds of needing a firearm to avoid harm are no different from the odds of harm you face getting out of bed in the morning.

I would change the words, "will not need" to "probably will not need."
Although this is no longer "The Wild West," nothing is certain.

Of the two times I really needed the pistol I carry, one of them happened right here on this bucolic, peaceful little island. Right at my own kitchen door, too.

I used to walk to and from work every day, right through the middle of the roughest, druggiest ghetto in the Los Angeles area. I was not allowed (by law) to carry a defensive firearm.
But I greeted everyone I met in passing with "Good morning!" or "Good afternoon!" Even the gang-bangin'est toughs responded well to that, and nobody ever gave me any trouble.
Usually by the second time I saw the same gangsta', he would smile and say "Good morning!" before I could even open my mouth.

Now that's funny, I don't care who you are......

Originally Posted by Steve M1911A1

Q: How do you protect yourself from bears?
A: Wear small bells that make continual noise as you walk, and carry a can of pepper spray for use in case of attack.

Q: How do you know whether bears are in your area?
A: Look on the ground for bear droppings.

Q: How can you tell if they are bear droppings?
A: Bear droppings smell of pepper spray, and contain little bells.

Originally Posted by berettabone

Now that's funny, I don't care who you are......

...Well, I care who I am!