Here is a list that I have compiled. I have tried many of them but not all. There are many more I am sure but these have been around awhile and have quality selections. Many are reference quality Masters.
These should get you started.
Good Luck!. . . . . ENJOY!
Archive.org has a lot of high res downloads of various live shows. Lots of high resolution available - including Hungry Lucy! and Calexico! Check it out!
Blue Coast Records
Bowers and Wilkins - Society of Sound
eClassical.com -- based in Sweden
Gimell Records (96k/24bit, 48k/24bit, 44.1k/16bit of the The Tallis Scholars)
High Res Music
High Definition Tape Transfers
High-res download test bench (free samples only)
NIN.com for those who like Nine Inch Nails