I know this is old but I had to respond anyway. No way should you sign a contract without checking out the company. If the job is pretty sizeable I would even check with your local governement entities regarding any violations or possble legal actions against the contractor. You don't want to find out after the fact that they've been in trouble before.
As CAS said, even if they are listed on Angie's List they may not have a good rating. Also, check with the BBB. All you'll see there is if the company has any complaints and if they were resolved but it is still good information. Always do your homework before doing business with someone.
Todd Shell
Todd's Home Services
www.thomeservices.com