How to find a Good Affiliate Program.

There are several ways to find good affiliate programs. I will not link with partners who pay under 10% per sale unless there is a bounty collected for a lead or clickthrough. I prefer to use commission Junction where you turn your traffic into profit . CJ.com has hundreds of affiliate partners and thousands of products that you can put on your site. The only thing is is that you have to sign up and apply to each program but if you have a good website approval should not be an issue. The nice thing is you get one check if you sell several items from different affiliates. There are other affiliate programs like this out on the internet but this is the one I prefer. You also want to find an affiliate partner who will have links that will fit into your web content or allow you to alter them to work into your content possibly even do redirects.
Also the higher the commission payout usually the harder the product is to promote or it may be overpriced but that is not always the case so research the affiliate you will partner with to see if they have competitive pricing.
A real good affiliate program is one that pays a good bounty and then pays 1 to 2 tiers down. The following is a good example of such a program...

RapidSatellite Pays you up to $100 for every system ordered, installed & activated. They will also pay you $10 per order generated by Referral Partners you refer to its Referral Rewards Program.ClickHere or http://www.rapidsatellite.com/a.asp?rapidsat&8703&0&affiliates.aspx

So you preferably want a hot product that will work with the content on your site and pays out over 10% commission on 1 to 2 tiers. The payout on the tiers is not really important and such programs can be hard to find but it allows you to generate residual income.