I, too, have always looked at ClickBank as a secondary and even tertiary monetization source. But it can be a great sources of revenue. I linked one of my articles to a related product on CB, and without really doing promotion or anything unusual, I get a few sales a week. Mind you, the keyword(s) for the post aren't that huge either. So, even though the traffic not huge on that post, it still manages to get some sales.
What kind of commission do they offer? One-time commissions or recurring commissions? For example, many programs pay you one time for sending a customer. On the other hand, some programs like membership sites or SaaS (software as a service) programs will pay you a commission as long as the person you referred is a paying customer. Recurring commissions are great when you can find them!
For a slightly different take on the subject and figuring out how to get targeted traffic onto your promoted links, you must have a look at Affiliate Marketing: Instant Traffic to Affiliate Links. A quick look at the reviews will help you decide if this is the exact course you are looking for. Sometimes the right approach is what is required to make a campaign work, this one might just work for you.
Affiliate marketing is also called "performance marketing", in reference to how sales employees are typically being compensated. Such employees are typically paid a commission for each sale they close, and sometimes are paid performance incentives for exceeding objectives. Affiliates are not employed by the advertiser whose products or services they promote, but the compensation models applied to affiliate marketing are very similar to the ones used for people in the advertisers' internal sales department.