Hey Ulf, from what I've been able to gather, modern icelandic and old norse differ in some considerable areas, but are very much alike in others. Since there is no record of how old norse sounded like, it has become sort of customary to adopt the modern pronunciation, and you can grab on to that if you're starting out with ON.
As for courses, there is the classic "Colloquial Icelandic" by Daisy L. Neimann, which is pretty much the only one out there, besides the "Teach Yourself Icelandic" by Hildur Jónsdottir... those two are the only ones I've been able to find that come with CDs. Sadly, if one has never studied germanic or scandinavian languages before, the tapes or CDs are almost invaluable because of the sounds and pronunciation of Icelandic is a great deal hard if you don't hear it spoken by a seasoned speaker.
However, I have found the course by Daisy L. Neimann a bit boring at times, especially because the speakers in the tapes talk incredibly fast, and you have to play and play and play them like a million times just to be able to catch what they say, which makes it pretty hard if, for example, you're planning on popping them in your car stereo or something like that (without the book in front). I've been at it for almost a year, and the progress is just WAY too slow...
I hope this helps in some way. If you or anybody else discover any new and STIMULATING courses with audio, PLEASE get back to me too!!!
 
David

__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com