Take a look at all the basic plans that have lots of space devoted to them over in Diet Central . . .
http://www.3fatchicks.com/forum/forumdisplay.php?f=102.
A lot of the GI/GL plans are popular right now (like Sugar Busters, South Beach, and many newer ones too). Weight Watchers is always a popular choice and some of the controlled Carb plans. A lot of people have great success adapting one of the popular plans to be more suitable for their own type of life.
Bottom line . . . do not think DIET . . . think LIFESTYLE CHANGE . . . that's pretty much the only way to be successful over the long haul. So you must find a way of eating that you feel you can do forever.
For me . . . it's a combination of a low GI/GL plan and Volumetrics . . . but because it works for me (albeit slowly) doesn't mean it is the best route for anyone else.
Good luck on finding your own winning combination . . .