I have been using adwords from google since i startup my website. I want to check out if google avoid indexing those site who pay them for adwords. My argument is if they index all pages and rank those pages, ppl would stop making adwords campaign
I doubt that is the case. If people know that using adwords would lead to not being indexed, they would not use ad words.
Adwords should be used in addition to normal SEO tactics. That way both aspects of PR strengthen each other. Adwords will not keep your site out of the serps. It won't get your site in the serps either.
I don't think AdWords has anything to do with site indexing. Point a few powerful backlinks to your site and you will be indexed in a day or two