Instruction for downloading Maps to a Garmin without using MapSource

NOTE: If you are using this method to upload a map to your GPS
through the USB, you must first install the Garmin USB driver
(this only has to be done once).  Garmin supplies this driver
free for their GPS at:
  http://www.garmin.com/support/blosp.jsp
  select your GPS model.  The USB driver should be on that web page.
This is not necessary if your are using the serial port for communication.

Double-click on GarminMBArea.exe.  An install-like program will
run and then upload the map to your GPS.
WARNING! This will erase all existing maps on your GPS and will
only allow you to install the map in the .exe.