I'm obviously not that familiar with Adscense but is there a way to determine what specific ad was clicked and where?
I think the OP means which actual ad NOT ad unit. In which case, as far as I am aware - there is no way
your can create channels for each site. also, you can create different channel for different position of your site. for example, if you do a channel for site abc.com, for the top position ad, you can call it top-abc or something, for the left menu ad, call it left-abc. you get the idea. now you will be able to track which ad from which site got the click
so, let me make the questions more deeper. is it OK to create a channel for each ads unit ? for now, i need it to see the effectiveness of each ads unit. many thanks in advance.
You can check it. Go and sign with ad logger, it is free. Then copy the code provided and paste it with the adsense code and then upload it to your server. That's all. When ever any click is there, it will be reported to the email provided by you during the registration