Clickbank is a well known site for downloadable products to promote. I like Shareasale or comission conjunction for physical products.
I must say Clickbank is the best affiliate site. It is used by above 100,000 affiliates to deliver their products and services at once in the internet. Affiliates can add any clickbank products to their site can get a commission on the sales.So I prefer Clickbank most.
Clickbank, Commission Junction, TradeDoubler - I would try them all, it's not much more complicated to work with more of them than to work with only one but you can gain more profit.
Most of us like ClickBank and I also like this. I think it is best for every one. I also like Commission Junction. This two are most popular.
I don't get why everyone is starting their reply with "is best" Were they supposed to give a name or something?
I have a little bit of success with Clickbank. However, I just did not try as hard. I did a couple article marketing for 2 products, and made over $2k in 2010. If I scaled it up, then I could have earned a lot more.
I have used Linkshare and CJ. They are both pretty good. I personally prefer adsense because I know I will at least get paid for a click.
The top 10 affiliate sites are EuroPoker, Betboo, CasinoRoom, AvaFX, Party Poker, Victor Chandler, EasyDate, Global Live Casino, AffiliateBOT.com and MedStore. I have found those by making search on google. I guess they are best.
Of course clickbank is best and very popular for affiliate programs but there are other options too. Search for it and know the difference