There are apparently a few people interested in getting it, so to save you the hassle of PMing me for a link you can download the backing track / instrumental / karoake / whatever you want to call it for Blue Sky here:
Two verses, like I recorded above:
http://www.4shared.com/mp3/PNDIKxhL/..._Two_Ver.html?
Three verse, like how Wario did it:
http://www.4shared.com/mp3/cu50prZ_/..._Three_V.html?
My revised cover, after Rob's feedback and Wario's inspirational cover :P
http://www.4shared.com/mp3/mcxKzeFY/...Revised_.html?
Enjoy!