The site is really easy to navigate, and there are two ways to go about it. You can click on the city index site map and view a list of US states and then a detailed list of cities within each state. The list includes suburbs and smaller cities--I come from a smallish city and found that city listed in the index. Once you've selected your city, you can find a list of categories for different types of home building and repair work.
The other way to navigate the site is to click choose a category, and then once you find your category and subcategory, you submit your details to receive quotes from local contractors. Part of what you submit is your zip code, which is what narrows the quotes to locals.
I tried out the site by searching for someone to paint the outside of my house. I found my city, selected the "exterior" work category, and then selected "exterior paint contractors." I only had to answer a few questions about the size of the job and any special conditions about my house (cracked or peeling paint, type of exterior surface such as siding or stucco, etc).
This is a cool and free site that is easy to use. Sometimes I can get referrals from friends for work on my house, but other times I can't. It's nice to answer a couple of quick questions and have contractors contact me, rather than making a lot of phone calls myself. The site is definitely worth a try, whether you're looking to get an energy audit for your house, having work done on your HVAC system, having an addition put on your house, or remodeling a single room.