Unlike other review sites, Angie's List membership (free) requires credit card verification from their reviewing members. This means that before posting a review your identity is verified. Because of this step, phony reviews (from friends, relatives the owner of a company or even competitors) are far less likely.
Another popular reviewing site is Yelp. It's free, but poyentially not as reliable as Angie's List (but better than nothing). Angie's List's focus is solely on service providers, while Yelp is more often regarded as a restaurant review site that also has service providers. Most other sites deem a service provider to be qualified when they pay for leads (Home Advisor).
While we have great reviews on both sites, we are most proud to have earned over 100 "A" ratings on Angie's List. We have also again been designated an Angie's List Super Service Provider, an award given based on our ranking in the top 5% of all companies in the painting category. This is not something a company can buy, it only comes from real, verified member reviews. We are happy to have received this honor each year we've been on Anhgie's List.
A newer (free) site that is worth checking out is Next Door. It's neighborhood/sub-division based and uses people's full names. It's a forum for neighbor's to share information, certainly not focused on reviews though you can ask neighbor's for referrals.