The best bet with products is to decide what people are more likely to buy online. Books and CDs are safe bets and attract a large slice of the affiliate market. Categories like hardware or big-ticket items are much more difficult to sell and often attract a low percentage.
Books and CDs
Amazon (www.amazon.com) and CDNOW (www.cdnow.com) are the big daddies of the affiliate programs and are probably some of the oldest. They offer CDs, videos, books (Amazon only) and other products. While CDNOW has the rare bonus that you can use your income as store credit if you wish, the detailed reporting at Amazon makes it easier to track and optimise your links.
The choices for linking are simple - you can link to the home page, genre or product group, or a particular CD or book. If, for example, the subject of your site is raising children, then you could link to parenting books on some pages, toys on others and maybe CD-ROMS for children on another.
CDNOW pays a flat rate of 5 per cent for music sold through your link regardless of what you are linking to, whereas Amazon pays on a sliding scale. The most lucrative items are the direct links to books - a generic link to Amazon's home page will earn you 5 per cent on a sale, but a link to a specific book will attract a 15 per cent rate if the book is purchased. A book bought for $US30 will earn $US4.50 - about $7 in Australian currency. To earn $US4.50 in banner ad click-throughs would require up to 10,000 impressions. This illustrates how a low-volume, carefully targeted site can still generate an income.