Don't make 1 ad and jam it with 9,000 keywords as the title of your ad, text of your ad and landing page of your site is kinda all rated for relevancy. Ads that get good ratings and good clicks can stay at your current bid prices as long as they are in the current bidding range they suggest. If your ads are overstuffed with keywords and unrelated text or your landing page sucks then you will see your ratings drop and as those drop you need to keep raising your bid to stay listed. I would say make a separate ad for each item you are promoting so each ad can be as highly targeted and relevant as possible to stay in competition with your current bid price and to keep your relevancy rank up. There is a learning curve and sometimes it will frustrate you but as you see what I'm talking about with the scores and relevancy being rated over time you should pick it up and get better at it. Depends what you are promoting as far as alternatives go but as far as general search engine traffic goes google is really supreme but a lot of people quit or hire people to run their ads as they get frustrated trying to figure it out. Other forms of marketing could be social facebook, twitter etc... or domain marketing buying keyword .coms that describe the exact product or service you sell. I do a little bit of everything. good luck
