How can I find bestsellers on clickbank?

There used to be a site called cbtrends.com , not sure they are still operational right now . Anyway, they rank products based on the gravity(how well they sell).

the higher the gravity, the more of a best seller it is

---> http://www.clickbank.com/marketplace.htm---> Choose your category---> Sort by gravity

A rough picture of what i mean
Clickbank Best sellers

But you want to be careful though . Some very high clickbank best sellers with 1000 gravity maybe a result of an army jv endorsements who have relationships with buyers on their list not neccessarily a prefect reflection of the results you would get if you don't have a list or haven't yet managed to get your subscribers to respond

Check out CBengine.

They have performance data and statistics on ClickBank products. You can search for products by rank, gravity, category, etc.

You can't.

This information is not made available by ClickBank. To anyone.

There are two specific points worth being aware of, in this regard ...

(i) Other sites who claim magically to be working this "information" out from their own "secret proprietary formula" (i.e. they won't tell you how they do it, surprise surprise) are typically talking out of their assets - they have access to no information that you and I don't have, and however "official" and "impressive" their websites look, they're dealing with complete guesswork;

(ii) The number of sales made of individual ClickBank products is one of the many components of the ClickBank algorithm which calculates each product's "popularity score" (but note that how many other inputs there are and what weight is given to each isn't disclosed), so there's arguably a very tenuous inference that at least some "high popularity products" may sell more than some "low popularity products", though the mechanism of this isn't disclosed ... and "gravity" (which is actually very clearly defined) really doesn't relate to numbers of sales, it being very common for "low gravity products" to outsell "high gravity products".

Would you be wanting to find the best-selling products to promote them, or to avoid them?

I freely admit that my own strong preference, having made my living that way for the last couple of years or so, would tend to be the latter ... because I have no particular desire to compete with many hundreds of better-established affiliates some of whom will have four-figure daily PPC advertising budgets for the purpose ... "just saying".

The gravity is the number of affiliates promoting the product. It may be better to look at the popularity if looking to buy. If you want to promote, then use gravity. I see the CBtrends.com site is no longer available. .

Trial/Error. Gravity doesnt mean a thing, the most hyped products dont often sell well, and products which have extremely small gravity (5.0 etc.) can sell well.

It depends on many factors, your website/pre-sell some of them.

Hint: You have better chances to actually selling a "wart remedy" to people who want to get rid of warts as opposed to selling the next best "how to make money fast" product.
All you need is a site offering a SOLUTION for people who are in need of something or need to solve a problem ..whether that is health niche or computer niche etc.

CBengine... for free and search for high gravity products