The official publication for Swedish statutes, Svensk författningssamling (SFS), is only available in Swedish.
Some Swedish legislation in English is published in the Ministry publications series (Ds), for example the Swedish Penal Code (Ds 1999:36), the Local Government Act (Ds 2000:72 and Ds 2004:31), the Bankruptcy Act (Ds 1998:41), the Swedish Environmental Code (Ds 2000:61), the Swedish Code of Judicial Procedure (Ds 1998:65) and the Swedish Arbitration Act (Ds 1999:22). This series is kept in Archive 3 in the Dag Hammarskjöld and Law library. See also Ds 2001:7 (Swedish statutes in translation).
In the Dag Hammarskjöld and Law library you can also find some printed collections of Swedish legislation translated into English, for example:
These can be found by searching the library catalogue. Note that these translations don't necessarily represent the latest version of the legislation.
The preparatory acts are mostly available in Swedish only, although many Government Official Reports (SOU) have a summary in English. The printed publications are kept in Archive 3 on the basement floor of the Dag Hammarskjöld and Law library.
There are no official translations of cases from Swedish courts. The printed versions of the case collections (in Swedish) are kept in Archive 2 on the basement floor of the Dag Hammarskjöld and Law library. In Archive 2, you can also find the annual reports (with a summary in English) of the Parliamentary ombudsmen (JO).
Cases on Swedish labour law (translated, with comments) can be found in the book Swedish labour and employment law: cases and materials by Eklund et al. You can also find some summaries of Swedish case law in Communicating justice, providing legitimacy: the legal practices of Swedish administrative courts in cases regarding sickness cash benefit by Stendahl.