Can I find out how much people in a certain area (like Bloomington) spend every year on certain things (like eating in restaurants)?

Yes!  One very good source for data like this is the Woods and Poole MSA Profile.  This is a print resource located in the reference collection, at HC 106.82 .M8.  In it you can find statistics on population, employment, income, and retail sales in MSAs (Metropolitan Statistical Areas) across the country.  They also provide projected data to the year 2030, in five year increments.