A GM in a PbP I play in produced a very nice map using photoshop, a satellite map image from Google Maps, and the following website. Don't ask me how he did it, being as I'm computer use challenged, but I'm sure a smart guy like you can figure it out. Thanks, NC!
He used mkhexgrid. The website can be found here:
http://www.nomic.net/~uckelman/mkhexgrid/