Kevin11,
If you have not found it already, check out http://www.payperclicksearchengines.com for reviews.
One of the most helpful sites if your doing payper click search engines (PPCSE) is: http://www.advantagelistings.com/alliances.htm This site will show you who is partnering with what PPCSE and where you need to be rank wise, to show up on the other search engines.
Hope this helps,
Bingo