Hei Jimbosjet,
I moved to Norway 18 months ago from the UK. I have used all the CD's and self learning books, but they only really give you the basics. The only real way to learn is to speak Norwegian as much as you can. I suggest (as much as your girlfriends patience allows) that you only speak Norwegian at weekends. To start with the conversations will be pretty basic but you'll be amazed how quickly you will pick it up ! Also try this website
På vei - interaktive oppgaver
Good Luck
Wizo