I made this awhile ago, but it was delicious... Shrimp stock is surprisingly quick to make, and when you buy shrimp with the shells on, you conveniently already have all the ingredients.
It's definitely tastier than it looks. Recipe from Bitten.
The bitten blog post has oh-so-detailed directions on how to do the risotto, but none on how to do shrimp stock. It's easy:
Peel the shrimp that will go into your risotto; toss the shrimp in a bowl, and the shells in a medium-sized pot. Cover the shells with cold water; toss in part of an onion and maybe the stems from the basil, and bring to a boil. When it reaches a boil, turn the heat down and simmer until the water has turned pinkish and it starts tasting shrimp-y (a half hour or so). Add salt. That's it!
Incidentally, this is AMAZING the first night, and not very good as leftovers.