You need to be careful about transforming a photograph to a vector. There are several ways to do it in Photoshop (and in Illustrator) but most microstock sites will bounce you if it is obvious that it was a photograph first (they can ALWAYS tell!). They will also require you to submit a copy of the photograph that was transformed to vectors, and you need to prove (somehow) that YOU took the photograph, it cannot be copyrighted to someone else. Another potential problem for you would be that ALL paths need to be closed. Meaning, if you did a Live Trace you would have thousands (if not millions) of points and potentially many, many open paths that would need to be closed. There is an Illustrator plug-in that finds open paths but on a Live Trace, it would be a nightmare, so labor-intensive that it would never be worth it. It would be easier just to trace over your photograph, taking creative license to change the image enough to make it NOT look like a Live Trace.
I think your best bet is to stay away from converting photographs to vectors because they are rarely accepted at the microstocks (in my experience, and from what I've read on other forums).