off the top of my head
Woody Harrelson (cheers/actor) is a vegan who is very into raw foods and appears in raw food videos
Also US congressman, Dennis Kucinich, who ran for president in 2004 and 2008 is the only vegan in congress/the senate.
Albert Schweitzer was a vegetarian and so is Sanjaya of American idol fame (and his mamajaya/sister..in fact her mom brought him homemade vegetarian foods and protein shakes the whole time he was on the show ;)
I have not looked through it yet but here is a huge list of famous vegetarians
http://www.happycow.net/famous_vegetarians.html
and here
http://engforum.pravda.ru/archive/index.php/t-174591.html
on the first link if you do a search by hitting control key and f at same time, and then type actor or actress, musician or singer, it makes it easier to find them.