Mmm... hazelnuts and chocolate are my favorite combination. I didn't know there was such a thing as World Nutella Day. Who doesn't like Nutella? :) Except, of course, homemade is much better since it can be made with good quality ingredients and a lot less sugar.
My Christmas present for myself (it was the only thing I wanted) was to buy a 10 lb. bag of Freddy Guys roasted hazelnuts. They really are the best tasting hazelnuts I've had. When they first come, opening up the bag to smell those freshly roasted hazelnuts was complete heaven! http://freddyguys.com/
I've made hazelnut butter a couple of times (so good!), and was planning on making a homemade nutella recipe I found on a blog (didn't know Elana had one, too), but have been baking so many new recipes out of the almond flour cookbook, that I've been satisfying my chocolate cravings that way and have put off making the nutella.
Wish I could come to your party--what a great idea!