If you are planning a party to coincide with the release of the final Harry Potter movie, I have a few resources for you in terms of finding some great Harry Potter recipes.
If it is Harry Potter's butterbeer you are after, you should check out What Is The Best Recipe For Harry Potter Butterbeer and, if you are like me, you would LOVE to buy some of these butterbeer steins on eBay.
If it is Pumpkin Juice you are after, you should visit What Is Pumpkin Juice where you will find more information about this Harry Potter drink and some recipe links. I was surprised to see that you can actually by a Kindle book called Butterbeer Recipes on Amazon for under $4.
If it is some candy confections you would like, you will find some excellent sweet treats available from chocolate frogs to Bertie Bott's Every Flavor Beans. (Thanks to Buzznet for this fantastic picture of Bertie Bott's Beans.)
The final and perhaps best resource for recipes for your Harry Potter party would be The Unofficial Harry Potter Cookbook. It is a lovely hardcover book packed with recipes for many of the treats you have learned about over the years in the books. Naturally, it features chapters on everything from Delights Down Diagon Alley to Treats From The Train to Recipes From a Giant and an Elf. I am certain you will find all the recipes you need to create a feast Harry Potter style for your Dining Hall.
at the movies!