From a UDI annual report for 2011:

9 900 people were granted their first residence permit to work in Norway.

86 per cent of applications were approved. Nationals of Romania, India and Bulgaria were granted the highest number of permits to work in Norway.

Most immigrants come to work in agriculture and fish-processing, industry or commerce, and the hotel and restaurant industry.

In addition, 36 900 EEA nationals registered as employees, jobseekers, self-employed persons or service providers.

http://www.udi.no/Norwegian-Directorate-of-Immigration/Annual-Report-2011/Work-and-residence/How-many-people-came-here-to-work/