How to detect click fraud

[Dlocks]

As an advertiser I'm looking for a solution to detect click fraud.

I have found some websites offering click fraud detection solutions. For example:

www.clickforensics.com
www.onestat.com
www.vericlix.com
www.doogleonduty.com
www.trafficsentry.com

And more...

I'm advertising via a lot of different PPC networks and would like to be able to create reports per PPC network containing 'proof' of click fraud that is excepted by most PPC networks (in order to get a refund and/or to block fraudulent traffic sources within a network).

Has anyone tested and/or still using click fraud detection solution? Any recommendations?

[qualibid]

www.clickforensics.com seems to be one of the most popular services but in our experience CF score has very little to do with our own click fraud tests. I wouldn't trust 3rd party services.

[simonbuzz12]

the best thing to do is to check your analytics regularly to see if their's any suspicious activity on your site once found report to google about it that way you will be fine...