First congratulations! I am an OR nurse too. I live in a state that doesn't require CEUs, but understand that certifications often do. Every year there is a free conference in my city put on by the American Cancer Society that is free, check their website, and get on a mailing list. I would imagine that they do this throughout the US. The conference is 1/2 day, and is held at a local hotel. There are a variety of professionals that attend, so not all is pertinent to nursing, but I have enjoyed attending.
Also check out your local technical school, I have found very reasonable one day conferences, 30-40.00/day, including lunch.