Ask HN: What is the best keyword tool for AdWords?
Wordstream? Wordtracker? Something else?
I also recommend not broad matching, and just using the words you specifically pick. Stay away from short terms, i.e. "backup" and go for one's like "complete backup". Also, don't use the content network for things you want people to take action on. If people are taking action, they're much more likely searching than browsing a page and clicking adsense. There are exceptions like video games and appeals to do other leisurely things in which the content network is actually better. Think about your users and where you're likely to find them. :)