If it is going to be a house gun more than a carry gun, I would recommend getting a gun with a rail so that you can mount a light to the gun, if something goes bump in the night, you can grab the gun with a light, instead of having to find both the gun and the light. I know you're asking specifically about a MILSPEC, but I just thought I'd throw that out there, unfortunately the only railed 1911 of similar price to the MILSPEC is the Taurus PT1911 of which I am not a fan. So if you decide you do want a rail, you'll probably end up spending more $$$.
Regarding carry, you first have two primary choices:
In the Waist Band or Out of the Waist Band
I carried my 5" 1911 in a Galco Avenger for many years when I chose to carry OWB.
When it comes to IWB there are many fine IWB holsters , my one recommendation is to choose on with widely spaced, offset loops to better distribute the weight of the gun.
Some good choices are:
Comp-Tac (Various Models)
CrossBreed Holsters (Super Tuck)
Desibens Gunleather (#2 and #3)
FIST (Various Models)
HBE (COM III)
Milt Sparks (VMII)
Tucker Gunleather (Various Models)
There are a wide variety of attachment options, I prefer leather snap loops, but that's just a personal preference.
Pending on how you want to carry, there are other options such as shoulder holsters etc. but the two most basic modes of carry are OWB and IWB.
The Springfield MILSPEC is a solid gun, it lacks most if not all of the bells and whistles of other guns, but is still better equipped than the GI models as the MILSPEC does have larger sights. However, you may not want or need all of the bells and whistles and if that's the case, the MILSPEC is perfect for you. Later on down the road, if you do want to change something, the MILSPEC is a good gun to be used as a base for upgrades.