I have found yelp.com very useful for finding mechanics, AC technicians, and RV service centers, in addition to restaurants. I was recently at a Norcold Service Center and the 5 yelp reviews were dead on. I also had a problem with a local plumbing company at my house and later I read the Yelp reviews and realized that they had a terrible reputation that was well deserved. Now I check it in advance.
If you use Google Maps and have it set for your location you can do a search nearby for a type of business and the ones retrieved will often have reviews indicated that you can check.
