There are many ways to sign up to be an affiliate partner with a site. Some companies manage their own affiliate programs. If this is the case, you need to sign up with them directly (if you know a company has an affiliate program, look on their web site for sign-up instructions). Other companies use someone like ValueClick or LinkShare to manage their affiliate programs for them (these companies provide affiliate marketing tips, payment consolidation services, advertising recommendations, and other services to both the sponsor site and the affiliate site). Affiliate marketing is a growing business as companies realize how profitable it can be for them to participate.