There are some maps available at Mapopolis.com ... they've got maps for palm pilot software ... their platinum plus gps maps are $10, and they're from NavTech ... accurate enough to do door-to-door directions, streets and addresses, water, landmarks, etc...

Do you think you can reverse engineer one of these into something usable? I've got one of their older free maps of dallas, I could send it to you if you like.

The maps are of US and Canada only right now ...

Also, I've got Microsoft Streets as well as Rand McNally's Streetfinder maps. Both of these have GPS support and driving directions. They also know about one way streets.

If you like I can send you some of this data, or a whole ISO image if you prefer.

Greg