Learning the Ropes
If you are shooting bullseye league (rimfire & centerfire only) you can get by with a Ruger MK II and a 1911. I know some bullseye league shooters who use a revolver, usually a S&W 38 for centerfire. It you are just getting into bullseye, most any centerfire will do. Some will tell you to get a 1911 because of the rapid and timed firing stages. I know a number of shooters that use a revolver, single action for slow, timed and rapid fire. Here's my recommendation:
Once you get into bullseye shooting, you may want to compete in NRA 2700 matches. A Ruger MK II and a 1911 with adjustable rear sight are all you need gun-wise. Start there, talk to the folks you shoot with, take a look at their range setup, range box, scope, ammo, and add the extras later. My first 2700 match, I took a Ruger MkII, a 1911, ammo, and a cooler with water. Shot all day with iron sights and ball ammo. Had to borrow a pen, have someone teach me how to score, borrow a stapler and pasters for the targets. I was green as grass, but I watched, listen and asked questions. The folks at the range took the time to teach me the ropes and never once did someone say "that's a dumb question".