Hey if you are still planning, Boiled shrimp is an excellant choice. You can by it by the bags already cooked at WalMart, (one bag for 20 people)$10.00 med. size. Get a very large glass bowl like a martini or margarita glass(WalMart) and put ice in the bottom then chopped celery, then cocktail sauce and then add chilled shrimp. Made to look like giant Shrimp Cocktails. These are great eye pleasers.