2 sec responseBusiness Data Tools : http://www.census.gov/data/data-tools/cbb.html
3 min read + 2 min video:
In graduate school, one of the things I learned about giving presentations was to "know your audience". This is very relevant to know as you can adjust your story and the presentation style to match the needs of high school students or undergraduate sophomores or a room full of post docs | professors | subject matter experts.
I learned to apply the same principle when it came to selling products or services. Know your audience, translates to "know your customers, potential customers". Where students and scholars look for knowledge alone, customers might look for knowledge and a product, or just the product, or just the knowledge alone.
In any case, it is crucial for you to know who your market segment is and how they are spread out through geographical or other territory. A great way to find a lot of such information is through maps. If I wanted to look at age groups, then I look at US Census data.
Below, I picked five major metro areas (Pennsylvania as it is a home state and other just out of certain trade considerations for a product under development. Here's a comparison of five states from US Census Bureau.
Clicking the different tabs on the map yields the comparison data for different parameters. It is interactive, go ahead and check it out.
Make your own map at http://www.census.gov/2010census/popmap/