Niche Pay Per Click Engines

Some recent Pay Per Click auctions on eBay:

The Art of Pay per Click Advertising by Willie Wheeler (2016, Paperback)

$13.98
End Date: Wednesday Dec-20-2017 10:55:56 PST
Buy It Now for only: $13.98
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Ultimate Guide to Pay-Per-Click Advertising (Ultimate Series) by Richard Stokes
$32.56
End Date: Saturday Dec-2-2017 18:07:04 PST
Buy It Now for only: $32.56
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Pay-per-Click Search Advertising
$4.18
End Date: Sunday Dec-3-2017 1:02:36 PST
Buy It Now for only: $4.18
Buy It Now | Add to watch list