This can help your prospect clients find where your business exactly located. They can also get some useful information from your business listing, such us phone numbers and read some reviews and testimonials from the previous clients of your business.
There are two types of business listing advertisement and these advertisement can be free or paid but whichever type you choose for your business will surely help you gain credibility in local search. However, the competition in free and paid is far different and mostly, the paid ones are the most often to receive unique visitors than free advertisement.
If you feel like paid advertising will bring success in your business, you may try http://listings.local.yahoo.com and http://places.google.com/business. But if you don't feel like spending some cash for your online advertisement, you may try free local business directory websites like Yelp.com,Whitepages.com and Local.com.
In SEO, local business listing is one of the important and critical ways of link building techniques. It is also one example of White Hat SEO which Google always promote to help people find exactly what they are looking for. Local business listing is not easy to spam and probably cannot be spammed because it is highly moderated and few information must be provided correctly before a post becomes live online.