You can use FitDay for any foods that you can get the nutritional information for. They have a large database of foods, some brand and some generic, and then you can also create custom food entries for things you eat often. Also, dietfacts.com has a large database of foods, and most of them can be added to FitDay with a button at the bottom. Both places offer free accounts.
I chose Core because at the time, I had been eating low-carb and my WW leader told us it was a "WW version of South Beach". I know now that's not exactly true, but I suppose it was the only way she could think of to describe it. Basically it included whole, unprocessed foods. There are several other plans now that are pretty much the same but have a few differences. If I had it to do all over again, and had available THEN all the choices that are available NOW, I would have probably chosen to follow
SugarBusters. I have an extensive family history of diabetes, and this is a recommended plan for that as well as for weight loss. One thing you have to remember is that Core uses all FF dairy, and FF has more sugar than lowfat or regular. Also, Core allows corn and white potatoes, which are both pretty high on the GI index and a trigger food for lots of people, so if those are dangerous foods (like you get started and can't stop!), you might want to stay away from them.
The Sonoma diet is another good one that you should check out. Also, there are several good books, such as
SuperFoods Rx by Steven Pratt, M.D. or
You: On a Diet by Drs. Michael Roizen and Mehmet Oz. The links will take you to the different discussion areas where you can talk to people following the different plans and get an idea of what they're all about.