Just started in IDPA. Shot first match on Sunday. Score was nothing great, but the fun shoot was well worth it. I shot the match with my XDm 9mm Compact and all the stock gear that came with it, holster, mag holder, and magazines.
The intent of IDPA is to allow shooters to compare their skill level without distorting the comparison with super gear. You should shoot what you carry (if you can carry) or what you keep around the house for defense.
My plan is to use the IDPA matches as just practice doing things I can't do at my normal indoor range. Rapid fire, movement, target transitions, etc. I expect to get better as I go, but I'm just competing with my last score.
I can say one thing about IDPA, at least the club I've gotten into: They have zero SNOBS (Shooters with No Observable Basic Social skills). Everybody is willing to help without being condescending.
If you're still looking for a place to try, I'd recommend IDPA. Lots of clubs across the country. Not a lot of cost to join. The matches only cost you a range fee and your ammo that you bring with you. Same as a day at the range, but they set up a LOT more interesting targets!