There are fascimiles at IMSLP, both of the 1589 edition (published as four part-books) and of a 1627 reprint, which has all the parts in the one book. Il Bianco e dolce cigno is the first song in each book.
The gentle white swan dies singing, and I, moaning, reach the end of my life. Strange and contrary fortune, that he dies comfortless, and I die blessed. A death that in dying, fills me with joy and desire. If in dying I felt no other sorrow I would be happy to die a thousand deaths a day.
This is a famous piece, so there are many, many recordings just on Youtube. The one by the King's Singers is a favourite of mine.
There are mp3s to help learn individual lines on the Southron Gaard music page.
Here are midis (in G) with all the parts present, but with a different line emphasised in each:
We usually sing this in G (a tone higher than the original).
- Il Bianco e dolce cigno, in G, (pdf)
There is sheet music in the Southron Gaard Songbook, the Cantiones Secundae (p54). It's in A-flat (four flats), a third higher than the original, which is in F (one flat). There's also sheet music at the Choral Public Domain Wiki, in several keys.
A rough guide to the pronunciation, in 16th-century Italian.
I prepared these guides using:
McGee, Rigg and Klauser (eds), Singing Early Music, chapter 13, "Italian", Gianrenzo P. Clivio, pp 187-211, Indiana UP, 1996.
Any mistakes and inaccuracies are of course mine (Katherina Weyssin/Katherine Davies, December 2012).