Hi,
Here is a few links for Brandenburg:
http://www.youtube.com/watch?v=hXBmygI-N3M
http://www.youtube.com/watch?v=Of1hK1Zae6s
http://en.wikipedia.org/wiki/Brandenburg_concertos
http://www.classicistranieri.com/public/post/johann-sebastian-bach-i-sei-concerti-brandeburghesi-7870.asp (Let me know if this one works for you - it played the whole movement on my Windows Media player!)
:)
~Ms. Silberman