Perhaps UserTesting coupled with a good UX consultant might be a good fit for you.
UserTesting will get you feedback very quickly, and a good UX consultant will be able to help you avoid a lot of pitfalls and help set you in the right direction.
http://www.usertesting.com/
I know of a handful of really good UX professionals and could see if they'd be interested in some moonlighting work if that seems like something that would be of interest to you.
-Patrick.