My sleeve was done Feb 18 2009 & man oh man I had a hard time... I was taking everything under the sun... Fiber, laxatives, stool softeners, - you name it... I was eating lots of fruits & veggies, and of course my protein and Water. Understand that you will not have as many bowel movements as you did before surgery - my dietician said that is normal.
Make sure that you are also getting enough FAT in your diet. It seemed that I was not getting enough. It took about a month but I am ok now... That was a hard time for me... I felt aweful. I found that all the meat that I was eating, the veggies, the fruit and the water had NO FAT or very very low fat. Who knew how much FAT played a role like that?!?!?!?
So if you are doing everything right - try adding a bit more FAT. Talk to your dietician & bring your food journal! They are the best people to tell you what it is that you need to change.
That was my experience. :)