I have a couple of friends who vomit a lot due to bulimia and they have yellow rotting teeth and scaly dry hands due to the stomach acid coming up. It can also damage your oesophagus, so definitely not one to be trying.
Putting this in perspective, in your last post you said you had overeaten - if this is a one-off then don't worry - it takes a lot of overeating to put weight on (just read any interview with Renee Z about the lengths she had to go to put weight on for the Bridget Jones films to see this).
If it is something you have done or intend to do long-term then you should really get help. By posting on here I suspect you know there is a problem, so you have taken the first step.
Please take action and get help to stop it now before it becomes a seroius problem:
http://www.bbc.co.uk/health/conditions/bulimia 1.shtml