First, make sure your state allows them, then be prepared for sticker shock. Suppressors are spendy and they are definitely NOT Hollywood quiet.
The $200 tax stamp goes to the BATF/NFA branch when you fill out the paperwork for the transfer after you "buy" the suppressor. The suppressor will remain at the dealer where you bought it until the stamp comes back, which can take from 4-12 weeks, sometimes longer depending on back log.
Suppressors are anywhere from $500-1100 and for the most part, the old saying "you get what you pay for" comes into play. Silencer Talk is a great place to start your research.
Good luck, but keep in mind, once you start going Title II, it'll become the most expensive habit you've ever had as you will want more (sbr's, FA, more suppressors)