Quite a few tech companies in Norway have an international staff and speak English in the office. I worked for a small Norway-based open source consultancy for a while. We spoke English in the office as most of us were not Norwegian and most Norwegian customers were happy to work with us in English. I spent some time working with QT Software (then part of Nokia) and their office was also English speaking IIRC.

Depends. Some companies do accept English speakers, but not all. I'd call them up about it before applying. Most accept Danish or Swedish, though. If you're just looking for a restaurant job, then most of them accept English only speakers. But that isn't to say that most customers do, so it helps to know at least the basics for your spesific trade. Sad fact: Norwegian is known to be notoriously hard to learn because most Norwegians resort to English with foreigners. So even if you come here, you might not hear the local language enough to actually learn it well.