our drama club had a hollywood themed banquet and basically we did everything in red black and white.people had to dress up as some famous movie star, musician or movie character (i was bjork...with the swan) we made all the center pieces to look like movie reels, loud speakers, and clapboards (they're made from cardboard ribbon spools and paint) sorry the picture's crappy but i wasnt aiming for the centerpeice when i took it.
i set up a backdrop so people could take memory pictures.
i believe we had a red carpet at the entrance and a sign that said hollywood above the door.also, a black and white balloon arch looks good AND occupies space which is always good.
for favors we bought small plastic champagne glasses, glued tiny bowties on the stems and filled them with kisses.
put cardboard stars all over the place, it looks really nice.
we always do a hall of fame thing, with a voting ballot and the winner of each category gets a gift that matches the category.i.e. most ditsy got a can of chicken of the sea (jessica simpson=ditsy) you get the idea.get a projector if it's possible and show a movie or a slideshow of everyone. as someone else said, you could have your parents or someone stand around with cameras and be annoying paparazzi.as far as themed food goes, i'd say don't worry about it other people won't care but if you really want you can make chocolate dipped strawberries that look like tuxedos or cookies that look like film reels.
Basically you can do anything with this theme so it's pretty easy and can be very low budget if you make everything.