PPC vs #1 listing

is it worth it for these terms

[puppetmaster]

I was wondering if anyone has any research on this.
I have some number one listing in google. I'm think about starting google adword account. Should I bid on terms where I have high placement? Is there a way to find out if people click on the adword first vs. the free listing?

thanks

[Robsp]

Puppetmaster,

See this thread for a discussion on your question:

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