Alaska DEMs

Heyo..

I am trying to import into GRASS a DEM of a section of Alaska which is in
arc-seconds and I am confused.

1) I can figure out the lat/long region borders by dividing the
arc-seconds by 3600, except for the eastern-most which is 0. How can this
be?

2) Could someone who has experience importing this kind of beast into
GRASS give me a clue what the process is? How do I set up the region? Can
m.dem.extract import a file in arc-seconds? Is there a program to convert
the arc-seconds to lat/long or UTM?

Thanks much!
-Nancy