You don’t necessarily have to have a huge site or lots of traffic. Consider emailing an affiliate program’s contact person (look for contact info on the site or in affiliate newsletters) if you send a lot of leads their way, rank well in the search engines for a related keyword or have a high conversion rate. Make your email compelling. Read my tips here. You just have to be a good fit and provide excellent value to the merchant. Another good resource for this is here.
Websites consisting mostly of affiliate links have previously held a negative reputation for underdelivering quality content. In 2005 there were active changes made by Google, where certain websites were labeled as "thin affiliates". Such websites were either removed from Google's index or were relocated within the results page (i.e., moved from the top-most results to a lower position). To avoid this categorization, affiliate marketer webmasters must create quality content on their websites that distinguishes their work from the work of spammers or banner farms, which only contain links leading to merchant sites.