The easiest way to make affiliate income for me is CPA (cost per action) offers from different CPA networks. Try Copeac.com, they have good support, forum, regular payouts.
You buy traffic at PPC and send it to Copeac's offers. For example, Copeac pays $3.5-$4 for every new person joined to dating site under your affiliate link. You can buy dating traffic (for keywords "dating online", "american singles" etc.) for $0.05-0.10/click on google adwords content network or using second tier PPC like Miva. Adwords search is really expensive now.
