Go to www.nisa-uspsa.org, its an IPSC affiliated club. If you are looking for an informal shooting with your piece, you can call The Outdoorsman at 1-847-746-1331. They are located at the IL/WI(Sheridan Rd.) border they hold a bowling pin shoot in winter but I don't know when they start again. They are not very particular about gun features, just come in shoot and enjoy! They also do an IPSC practice match(non-sanctioned) every Tuesday night 1700-20?. Also, do a search with keyword; "Pine Tree Pistol Club", I forgot their address. They are located at Rockford IL. They do some competition every month(Various types). 'hope this helps and safe shooting!
Any IPSC/USPSA club will allow you to compete. You will be shooting in Open class with all the other compensated guns, but you will be allowed to shoot.
You might check with a local IDPA club about being allowed to play. Some clubs let you shoot, just not for score against others. My IDPA club does just that. We put you in your own division. After all, you want to come out and shoot. Why should I tell you that you can’t even play just because IDPA doesn’t like your pistol. While I agree with most of the equipment rules, I let anyone shoot. If their equipment isn’t IDPA legal, you end up in a separate, non-IDPA legal class.