Google offers a beautiful interface for displaying the location of businesses. The result pages include zoomable maps.

E.g., Find cheap restaurants around Manhattan (http://www.google.com/local?q=cheap+restaurants&near=manhattan)

You can also get there with: http://local.google.com/
I've been using "Local" for a month or two now, because it helps me find businesses faster than digging out the right Yellow Pages book, and it also lets me zero in on my local area to find my direct business competition and places I can market my business better, based on local saturation of other similar fields.

Lets also not forget some of Google's other services, which don't get as much attention as they should: http://froogle.google.com/
Froogle is great for comparing the cheapest pricing for lots of gear. I use it, along with http://www.fatwallet.com and eBay to get a good idea of what a product "should" be selling for.
http://catalogs.google.com/
Another great Google offering, which does a visual OCR of physical (printed) catalog pages for your search terms. Pretty slick stuff.