I'm suspect that this may be what you are after - targetting sites from Adwords (not targetting sites from Adsense)
From Google Adwords
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Bid CPC on placement-targeted campaigns
Cost-per-click (CPC) bidding is now available for placement-targeted campaigns. Placement targeting (formerly site targeting) allows you to choose the parts of the Google content network where you want your ads to appear. Previously, you could only place bids on a cost-per-thousand impressions (CPM) basis when using placement targeting.
What's more, preferred cost bidding is now supported for both CPC and CPM bids in placement-targeted campaigns. After choosing the bid type that fits your needs, you can specify either the average price or the maximum price that you would like to pay for each click or 1,000 impressions.
Now you can select the sites on the Google content network where you want your ads to appear and choose the bidding option that best matches your advertising goals.
https://adwords.google.com/support/b...56282&hl=en_GB.
Regards
Richard