I am an IDPA match director.
Some clubs are unfortunately calling their shoots "IDPA" but are not affiliated IDPA clubs nor do they use actual IDPA rules.
So what you find depends a lot on where you go.
Here is a link to actual IDPA clubs:
International Defensive Pistol Association - Affiliated Club State and Country List
The actual IDPA rules are on this link:
http://www.idpa.com/Documents/IDPARuleBook2005.pdf
IDPA allows both paper and steel targets, with a
maximum range limit of 35 yards. 75% of all shots in a match must be 15 yds or less (pg 12 in rules). Most targets are the standard cardboard IDPA targets. Only 25% of the targets on a stage may be steel, and only 10% of the total targets in the match may be steel.
Scenario stages are limited to a maximum of 18 shots (not counting misses).
The dreaded standards stages are the exceptions to the scenario rules.
If you want to shoot IDPA, then
find an affiliated IDPA club and GO SHOOT.
I get totally frustrated with people who wait and wait, trying to get the "perfect rig" and get "good enough."
IDPA people welcome beginners, and your first time is going to be a blur anyway. You will learn more in a few club matches than anything you read or hear secondhand.
1. Be safe.
2. Have fun.