Visit your local carpet dealer and ask who he or she recommends to install carpet. Carpet dealers know the local installers and what kind of work they do on a regular basis.
Join an online referral service such as Angie's List. Angie's List charges fees to its members who submit reports on local businesses. You can log in, search for carpet installers in your area, then call a few installers and ask them to submit bids. Return to the site to tell others about your experience with the installer you hired. Angie's List charges a $10 signup fee plus monthly dues that vary by city but are typically less than $5.
You can also search the Internet for "home improvement referral" and the name of your city or state to find local referral services, such as The Home Works Solutions, Inc. site for California. Note that businesses may pay to be listed on sites where referral information is free. Online searches for ratings of carpet installers may turn up reviews that were written by paid rating writers, which is not the case for consumer-driven sites like Angie's list.
Ask family and friends who have recently had carpet installed by a local company. Find out if the work was completed on time, if there were any hidden costs, if the installers were professional and reliable, and if they would recommend them to you in general based on their experience.
Check the yellow pages. Search under "carpet" or "home improvement." Use the online yellow pages to find local installers and maps of their locations.