I have always found the Norwegian tribute (1993) to be one of the best, if not THE best Cohen tribute. (For more details check http://www.leonardcohenfiles.com/cover3.html )
I noticed that 30 sec sound samples of all tracks are available at http://www.musiconline.no/shop/displayAlbum.asp?id=2560
You may also buy single tracks for download, or the whole album (credit card payments accepted)
My personal favorite on the album is Who by Fire (Alle vet jo det) by Kari Bremnes.