There are many airlines flying to Oslo. Your best bet is checking flight searches such as KAYAK for up to date schedules and prices.
Once at Oslo Airport Gardermoen, catch a local NSB train to the city center. The express train Flytoget goes more often but is more expensive too. If you are flying to Torp or Rygge Airport the airport bus is your best choise.
Getting around in Oslo is easy with the public transport system. Ruter will give you all the information you need.
There are many hotels in Oslo.
Thon, Raddisson, Saga, Smarthotel just to name a few.
On average a single room costs about kr. 750,- per night, and a double Room kr. 900,- per night.
Trondheimsveien 2K, Oslo
Friday and Saturday party
OSLO HOUSE OF INNOVATION.
Skippergata 22, Oslo
Sunday tea dance
Youngs gate 6, 0181, Oslo