Routable OSM map of continental USA for Garmin?

Yes, I have a Garmin, and a large SD card. I’m trying to find a source for routable OSM maps that will install into Garmin’s Basecamp or Mapsource software (and then ultimately onto the Garmin device). I do know about the URLs below, but each has its issues. Can anyone please help me find (or build) what I’m looking for? I played with using the daveh file, plus MapSetToolkit and cGPSmapper, but it appears I need a “.tdm” file and some other stuff before I can get it all into Basecamp.

http://garmin.openstreetmap.nl/
http://daveh.dev.openstreetmap.org/garmin/Lambertus/

Thanks!

It’s a long time since you asked this question.

Did you try http://garmin.openstreetmap.nl/
Here you can either select “ready-to-use” maps for Garmin.
Or you have the opportunity to generate a map which is composed individualy.

For the US the states are ready-to-use.
Should you need more or all states together on the map you can generate it.

Normally the map is ready within a short period of time. But it’s depending on the load on the server.