I had my gallbladder removed in 2001. I had post surgery diarrhoea for about a week, then it settled down. I ate a relatively low fat diet and it seemed to stay stable for quite a long time. Over the years though, I've gradually become lactose intolerant and now I can only tolerate small amounts of fat at any one time. The problem appears to be that the gallbladder is a reservoir for bile, which is produced by the liver, and it concentrates and releases the bile into the intestine when needed to help digest fats. With no gallbladder, the bile drips constantly into the intestine straight from the liver. This is what I've been told anyway, and over the last two or three years I have developed quite severe IBS which I keep under control with medication. The best advice I can give you is to eat as low fat a diet as you can. If you have a natural health food shop near you, go in and ask their advice - there are some supplements you can take I think which help with the problem.
Good luck!! :)