Online resources
Cyberbass resources:
Cyberbass has an online service that lets you emphasize your part, and speed it up or slow it down, if you have an internet connection:
Bach BWV 1 - Wie schön leuchtet der Morgenstern (movements 1 and 6)
Bach BWV 61 - Nun kommt der Heiden Heiland (movements 1 and 6)
Monteverdi Vespers - all choral movements
Youtube (and similar) resources:
The internet does seem to have it all.
For something completely different, check out the performance by Horowitz of Busoni's piano transcription of Bach's organ prelude BWV 659 of "Nun kommt der Heiden Heiland", and see the suggested reading for Veni, redemptor gentium.
Because it is the 400th anniversary of the publication of the Monteverdi Vespers, more and more recordings are available for viewing on the internet. Here are some of the more interesting ones:
(a) The Savall and Tubéry videos include antiphons before most (Psalm) movements.
(b) Most of these miscellaneous videos were posted to youtube by "OedipusColoneus", without citation of the performing group.
(c) In the Gardiner videos, movements 5 and 6 are combined into one.
(d) The Magnificat movements are typically split into multiple parts, since youtube has a ten minute limit per video.