Where is the best places to find faculty job postings in physics?
If you're a member of the American Physical Society (APS), I would recommend looking there first (http://www.aps.org/careers/employment/index.cfm). Many universities will post here, as it's the official representative of physicists in the United States.

In addition, I recommend looking at university department webpages. If there is a certain region or state you'd like to work in, narrow your search to universities there.