Depends on your location. Here is a list of IDPA clubs in va.
http://www.idpa.com/clublist.asp?pick=VA
I'm in N. Va, and there are usually monthly matches at Silver Eagle Group as well as Blue Ridge Arsenal. SEG is having problems finding MD, so not sure when their next will be. Rivana gun club is supposed to have matches, as well as The Range down in Fredericksburg.
If you havent already, you might join this group, there are a few comp shooters there as well.
http://vagunforum.net/