My friend had a really adorable costume Alice in Wonderland tea party with desserts. I made strawberry marshmallows with the seeds in and you can make them alcoholic for a light buzz too. Pies, cakes, cheescakes are also a great choices, they are easier to handle and slice up and store. My favorite easy pie to make right now is Emeril's key lime pie. Brownies were also a big hit, I used the Baked recipe from NY and they are super dense and rich. If you want to serve something unusual to plate think about it in a tall shot glass. One other tip is that you can make your own serving platters by buying glass glue and glueing old plates to turned over small serving bowls. Be organized about it, remember fridge space and so many desserts can be made ahead of time. Try not to make anything that will melt sitting out, so you can ensure you enjoy your party and aren't just worried about finishing stuff or moving stuff.
I bake a lot now.. so if you are looking for specific dessert recipes or want one of the ones I mentioned I would be happy to pass whatever I know along. Happy early Birthday.. hope you have a great party!