Unlike the dwarves, who are actively involved in Norse myth (making artifacts, killing Kvasir and turning his blood into the mead of poetry, etc.) the alfs are on the sidelines for the most part.
They seem to be have been a noble or possible divine group, as they are often mentioned in poetry alongside the Aesir, or gods. (The cosmic poem Voluspa mentions them together, as in "How fare the Aesir, how fare the elves" as if they were somehow equivalent.) In Skirnirsmal, too, Gerdr asks Skirnir if he is an alf, or from the Aesir or Vanir (the two groups of gods).
Snorri talks about dark alfs and light alfs, but it's not clear if that was his own idea or part of Norse belief generally. They seem to have been a lot like Celtic fairies, who were morally ambivalent. This may have bothered Snorri, a Christian.
According to the Prose Edda, the god Freyr is ruler of the alfs, and was given Alfheim (the elves' home) as a tooth-gift, a Norse tradition. (Sort of like the tooth fairy in reverse, as you gave a gift for a baby's first tooth.) The poem Alvissmal gives various species' names for things, including some poetic ones from the alfs:
- " 'Heaven' men call it, | 'The Height' the gods,
The Wanes 'The Weaver of Winds';
Giants 'The Up-World,' | elves 'The Fair-Roof,'
The dwarfs 'The Dripping Hall.'"
If you want to know more about elves in Norse myth and folklore, here are some references. The Alaric Hall one is actually his thesis, with only one chapter on Norse elves, so you can skip the rest. The other is a paper. They include a lot of folklore and saga material about the elves, which you might find interesting.
Gunnell: “How Elvish were the Álfar?” in Constructing Nations, Reconstructing Myth: Essays in Honour of T. A. Shippey, Brepols Publishers: 111-30. (pdf here)
Hall, Alaric (2007). Elves in Anglo-Saxon England: Matters of Belief, Health, Gender and Identity. Anglo-Saxon Studies 8. Woodbridge, Suffolk / Rochester, New York: Boydell Press, 2007. (pdf here)