best method for increasing traffic

I would like to get traffic to my site as quickly as possible, or fairly quick, can you please tell me what the best method for increasing traffic to my site without spending tons of money. Also what are the best Pay Per click search engines that I should use if that is one of the options. Thanks

Pay Per Click for the last month

I've tried Overture Pay Per Click for the last month now but the thing that strikes me is I have no way of tracking sales per keyword. I have affiliate software which *could* do this but it would mean an affliate account for each keyword/phrase which would be ludicrous bearing in mind I am experimenting with about 20 to 30 keyword phrases and possibly looking at other Pay Per Click engines. Is there a recommended script that will do this (free or otherwise). What I'm looking for is software/script that will tell me Overture made a total of X in Y month, with a breakdown of each keyword/phrase sales. Any suggestions?