Wine 1.0 is out at last; so it's possible you can at last -- with
it or CrossoverOffice. If you do, please post how here, with a large
fanfare.
I have Garmins, with software from Garmin, Maptech, Topo.com, and
Delorme -- and I have <curse, snarl, screech> a machine I can run XP
on just for that.
Two or three years ago, I worked long and hard, with this list and
two or three others including CrossoverOffice, to manage under linux.
I managed to get two of the four suites of software to run under
Fedora -- but never did get any of them to talk to any of my Garmins.
There *are* also several linux-native apps -- if you're Alpha Plus
Technoid enough to use them. Last time I tried, it took not only a lot
more linux-savvy than I've got, but something like a graduate degree
in cartography besides.
Good luck! And please report in exhaustive detail. Pretty please.