Does anyone have any experience with this site for leads?

You pay a fixed rate per month, but there are no per lead fees.

Most of the lead providers, search the public information bases and resell what you can obtain at no charge.

Take a look at this example for public projects:
http://publicnoticeads.com/NJ/search/view.asp?T=PN&id=680\2192007_5863520.HTM

There are also sites for private construction bids.

The smaller jobs are usually sites that attract price shoppers, these may cost more to buy then they are worth.