I lived in Stockholm for 5 months for an Externship. It was an amazing place to live.
Everywhere in the city is a 15 minute walk, at most, from a subway station.
The locals took me to a pub that was undergound that served beer and mead in clay pitchers. You could get 4, 8 and 12 L pitchers of beer and mead. It is Medivel themed. Go There.. It is on Gamla Stan (the old town) and you can make it part of your tourist visit there.
http://www.ratemyarea.com/places/sj-tte-tunnan-109345
Some general tips.
1) Budget about 150% for groceries based on what it is here. Everything is more expensive and junk food has taxes on it.
2) Going out is expensive. Beer is about 8 or 9 bucks everywhere, but you can get it for 2 bucks at the Liquor store.
3) Have some pizza there. It is the Napoliatano style mostly and extremely tasty.
4) Do the Viking Line cruise from Stockholm to Helsinki ... It is an over-weekend cruise which costs about 50 bucks a person. Duty-free booze too .
5) Take a trip to Gothenburg.... amazing Gothic style architecture. Also, Take the train to Copenhagen (about 4 hours)... another beautiful city.
6) Get a monthly pass for the train (most convenience stores)... it is pricy, but not as bad as paying for each trip.
7) Check out a game of Bandy... think soccer mixed with field hockey on ice.
8) Check out the VASA museum on Djurgarden. It was the best museum i visited there.
9) Swedes are very reserved and quiet generally, but very respectful. They would actually switch to English while talking with their friends when i came around, even if I was not a part of the conversation.
10) The Absolute Ice bar is neat to see, but only once... it is quite expensive.
11) Get a full loaded Tunnebanna
GO !!! It is an amazing City with amazing people. You will really enjoy it.