An M1 Garand should be on your list
, just because.
Collecting is all up to you! I started because our only gun dealer in our village wouldn't order me an Ishy 2a so I got a C&R lisence and got it myself. Then because it was an Enfield and I could get rifles through the mail and I have five sons and two daughters so I thought they might like an Enfield too...
You need to be very cautious though that this new found freedom doesn't become an addiction. There used to be a thread just for Milsurp-o-holics where frustrations about the lack of funds or aquiring parts and pieces, or ammo, for guns you want but don't have yet could be vented. Members would try to talk you back onto the wagon, or enable you. Baby steps are good!
To answer your question about what to get; check out the internet auction sites and C&R dealer sites and watch them over time. You will get a feel, or a head ache from scrolling, or just see whats being traded and sold. Do some searches "Google is Your Friend" and TFL also. Check out some mostly C&R forum sites;