If you save your Basecamp/Mapsource file as a .gpx file (not .gdb), you can open the .gpx file with excel. You are going to get a few warning messages before the final file will open:
Open as an xml.
If you have tracks and routes in the…
Garmin BaseCamp is an application which enables you to view Garmin compatible maps on your Windows PC and Macintosh, do route planning and transfer waypoints, tracks and routes between your PC/Mac and your Garmin GPS device. This is a FREE application from Garmin and it will eventually replace MapSource.