I do Skeet, and clays, a little 3 gun.
begining 3 gun is surprisingly affordable, we have about 2 games a month locally.
If one is carefull and dilligent you can buy ammo and still compete and not break the bank, more shotgun that anything else (I use wally mart loads, cheaper than reloading)
Pistol and rifle anre reloading affairs if you get serious at all.
We have a box stock division in our local games, so a plain Iron sighted AR (mini 14 also) and a mav 88, plus a pistol(high cap helps but not manditory) and your in
If you dont have one of those, someone will loan you what yu lack but bring your own ammo.