There are several ways to do this. Most important is to "claim" your listings, which means verifying that the listing is yours. When you do this step, you are able to update your listing and control it.The next important thing to do is to make sure all your information is accurate and do the extras, like adding photos, etc is also a good ideal to put yourself in as many free resources as you can (Google maps, Yahoo local, Bing local, etc.An easy place to start and learn about how your business is doing is to use
http://getlisted.org which is a free tool that asks you to enter your business name and zip code and then it checks your listings out and scores it and makes suggestions of hoe to improve your listing rank.