Right, I am not a complete noob. The only competitions I have done is Coach's carry matches, so IDPA will be new to me. I am a fairly new shooter as well, sort of. I plan to have a good time and am looking forward to it.
Just make sure you don't show up with a hot weapon. All IDPA and USPSA matches are cold ranges. No Loaded weapons at any time unless under the supervision of a Range Officer.
You will have a great time. IDPA is a lot of fun!!