If you have questions, see first the mailing list archives:

  http://s2.selwerd.nl/~dirk-jan/gpsdrive/
  http://lists.gpsdrivers.org/pipermail/gpsdrive/
  http://www.nabble.com/GpsDrive-f14291.html
  http://news.gmane.org/gmane.comp.linux.gps

and the wiki collaborative help site:

  http://www.livingresource.net/gpsdrive/