My impression is no, but here goes: My blog: PR5, 25-30,000 uniques per month, currently get $18pm per link from *cough* no, I don't sell links! A link buyer approached me out of the blue with this offer: All links permanent, one price, to non-spammy in context sites. Format would be a sinle paragraph with three or four links embedded. Link from front page via custom paragraph in style of blog: $150 Link from individual pages: $15 each, with interest in three pages for now. One of the pages they are interested in is currently #2 for a phrase that gets 30-50 hits per day for now and could do 10 times or more next year. Even with TLA taking half the cut (not that I sell there, oh no) that $15 represents just three or four months' business, and I retain editorial control and the right to chase off customers if I get fed up with them.
you just got to think to yourself is a one time payment for a link on your site worth it. you could say that for $150 ill put a link up for 1 year after that you will have to ask again. Personally if i had ~2 for a certain phrase and was getting 50 hits or so a day $150 is very cheap. If say charge more personally but then im a tight git. People will pay what you ask them to pay as long as its not extortionate.
Selling text links is against Google TOS, I suggest finding another way to generate revenue with your site. If you read through some of the threads in the Google sub-forum you will see.
So, Google is the only company that can sell advertising? LOL. That interpretation is a misread. Google's TOS indicates you can't sell links to further your ranking. They don't say anything about selling links for advertising purposes. However, that is what causes the grey area -- who is selling links legitimately and who is selling/buying just for PR. Unless of course I misread your post or misread something else, you're out to lunch.