Search Engines look for specific information on your website to be sure about your professionalism and if they can trust the information displayed on your site.
There are some different sections you must have on your site:
- Contact Us
- About Us
- Terms & Conditions (Disclaimer, Privacy Policy)
- Site Map
The address of your business must be included in one of those sections and also be listed on dmoz.org. This website is a directory which has each new entry reviewed by an human being. If your site has an english version, you must be on this directory, as all the search engines read this site frequently, as they know they can trust the information given in a site that has been reviewed by a human.
Depending on your sector of activity, you might also put your address on every page. This is even truer if you want to return on Google Local. See also our section: ?How to optimize your listing for Google Local??