We use TechNet and do the studies ourselves.
Lehi City primarily uses info from TechNet, primarily because ease of access to Utah data and relatively low cost. In the past we have consulted out the wage study to Mike Swallow of TechNet/Personnel Systems and Service, but we actually did it in house this year. Maybe I am too much of a scrooge to pay for additional surveys, but I think we get by fine with what we have.
About 3 years ago, we changed our approach from 25 pay grades to each position has it's own pay range. It allows us to be more responsive to the market as not all positions are in the same demand. Last year we raised Building Inspectors pay by 10% because we weren't getting enough good candidates. It takes a little more research to find good comparables, so sometimes we use job families when Lehi City has unique positions. I'm happy to share more info if you are interested.
What compensation studies do you use to determine the "market"? Do you use a job classification system or does each job get treated individually with a market average?