I bet you're already ahead of me here. What helped me was getting involved in the various magic clubs in the area. I began competing with adults in the local IBM and SAM club meetings, I learned a lot in the process. The competitions that they held were few and far between though.
From what I know of your past posts you sound like you've been very active with the Magic Castle. I'm sure that helps a lot. I have the feeling that you're looking for larger competitions.