Local club matches are generally pretty casual. A sanctioned match will always have a chronograph stage. It's pretty easy to make PF with most normal loadings in 9mm/.38 and above. Power Factor is calculated:
Velocity x Bullet weight
---------------------
1000
Just show up at your local club with your unloaded weapon in a good strongside holster, and at LEAST 3 magazines or speed loaders, with the approporate pouches, along with ear/eye protection, ready to have FUN!!! Let them know that you are a first time shooter. They'll brief you on what you need to know, and have you sign a waiver of liability. It's a good idea to go to the IDPA web site and learn the range commands and basic rules before hand. I haven't seen anyone who likes to shoot, fail to have a great time.
Enjoy,
Savage