When i first started with google I lost alot of money because I was bidding on real common search terms such as "web hosting" ect ect and was paying about $2 per click and i wasnt even in the top place i was about 7th position. Now im bidding on search terms that arnt as common and that other web host arnt bidding on and im bidding on alot of search terms. I dont get as mcuh click thrus as i used to and am paying a maximum of 10c per click but about 75% of the clicks generate sales so thats ok.
Overtrue is the cheaper way to go but i dont know how effective they are.
I hope what I just said makes sense
Wayne