Lots of places like coffee shops have hot spots -- these are essentially just places with wireless routers like yours. Some places provide it for free, some places charge (Starbucks charges, for instance). I'm sure someone has listed the free places in your area somewhere on the web.
One thing you should know is that most of these places don't use encryption (WEP), so any internet stuff you do that isn't encrypted is essentially being broadcast for whoever wants to listen. Web browsing is encrypted for https URLs, but not http URLs, and most POP email servers don't use encryption.
Some cell phone providers have a wireless card & service that uses the cell network. I know Verizon does in the San Diego area. It's probably somewhere in the $40-80/month range.