I want to roll a beta test session for my iphone and ipad application with general public. Want to get some feedback before officially launching the app. Does anyone know of a a good community that I can tap into?
I found http://ibetatest.com via google but not sure how good/bad it is?
Not sure you can. I believe Apple limits your beta test deployment to less than 100 and they each have to provide you with their device ID which you then have to register which won't make it that easy for a 'general public' type test.
As for finding a particular community, it'd really depend on the demographic your app is trying to target.
I found the best results came form posting on forums. You get people who are actually interested, you don't have to pay and you give your app a little pre-release PR. Try the macrumors forums.