Where can I get pizza data I'm studying the pizza market, especially in Utah, and I would like to know if there are any pizza data sources. Can some kind of sales tax data be used to study pizza? Is there a straight up pizza study that collected data? How creative do I have to get to find data? Or how much might I need to pay to have someone collect it?

Any data related to these things will be awesome: pizza input markets, pizza production, pizza demand, pizza labor, pizza firms, anything pizza and economics.

I'm not sure exactly what variables I'm after, I was just going to see which are out there first. I put in a request to Yelp.com to get access to their data sets, but it's only allowed for a few universities right now, not mine. We're on a wait list. Other than that, I'm kind of stumped.
It might not get you very far, but a start would be Google Trends: