<soapbox>
The initial install for debian is sometimes gets new users a bit discouraged, I haven't done one in a while, so maybe things have improved by now.

However, once you have it up and running, it is trivial to keep it up-to-date, which is why I haven't had to 're-install' anything from scratch over the past couple of years.
</soapbox>

When I was setting up my cross-compilation environment, I put all the steps I took in a script that hopefully can install the same toolkit automatically. Just follow the gpsapp link and it should be at the bottom of the page.