Hey there, nls35,
I had my gallbladder removed about ten years ago. My weight did go up, but I don't think it was because of the gallbladder removal, although perhaps some of it was. I think my "genes" are also just set to do that--get heavier as I get older--and so I've come to realize, after losing and gaining and losing and gaining, etc., that I just am going to have to pay attention to what I eat in a way that I never had to when I was young.
I myself don't do well at all on a vegetarian diet. My ancestry is all northern European, and you know, those folks didn't historically eat a lot of soybeans.

I do much better eating adequate animal protein, mostly chicken and fish. It's the carbohydrates and fats that I really have to watch!
Just about any food these days has nutrition information on it, and even if you aren't in practice on calorie counting, you can see what you're getting in a serving. And watch the serving size! It's a simple matter to keep a running tally in a notebook.
Or, you can try the FitDay calculator that's available on the web. It has a lot of foods already loaded into it, and you just type in what you had and how much. It does all the math for you. There are other tools like that on the web also. The only drawback to FitDay for me is that it overestimates how many calories I burn in a day, so I have to adjust that downward.
Lots of good information on 3FatChicks also about different food plans! Be sure to check out the resources.
Jay
Highest weight: 198
Current weight: 182
Goal weight: 155