Lillestrøm SK was awarded a Uefa Cup spot, so they enter in the 1st qualifying round I'm guessing.
So the list is:
Rosenborg BK (TL06 1st place) - Champions League (2nd QF round)
SK Brann (TL06 2nd place) - Uefa Cup (1st QF round)
Vålerenga IF (TL06 3rd place) - Uefa Cup (1st QF round)
Lillestrøm SK (TL06 4th place) - Uefa Cup (1st QF round)
Fredrikstad FK (TL06 8th place, Norwegian Cup 1st place) - Uefa Cup (1st QF round)
Rosenborg are seeded in the 2nd QF round and unseeded in the 3rd QF round, and as far as I know neither Brann nor the other three Norwegian clubs are seeded. Rosenborg has a strong squad, have a long CL tradition and are always in with a shout.
Brann has a strong squad with several players with international experience, but are very moody. Brann can play excellent when they want, but are traditional underachievers so I'm not holding my breath for a place in the group stage as we usually stumble against lesser opponents.
Vålerenga has one of the strongest squads in the league, won the league in 2005, but are playing sub-par and is a bottom team at the moment.
Fredrikstad FK is a typical mid to bottom table team, OK at home and weak away. However FFK have strong traditions both in league and cup, they've just opened a new stadium and has a faithful crowd behind them, maybe this can aid in their European quest.
Lillestrøm has a decent looking squad and are playing well in the league at the moment, main reason is their new manager, Tom Nordlie, who is a big fan of hard work.