Well, most of the time all you need to do in return is provide a link back to their service from your site. Read the FAQ page for more information on adding these extras to your site. Keep your information current and change content frequently. No one likes to visit a site with outdated material or one that always stays the same. Keep you image size down.
Large images increase load time.
People don't like to sit minutes for a page to load. Supply as much information that you can. Many times people would rather look on a Web site for information than call for it. Give them what they are looking for. The more information the better.