First I recognize the Xeno-Canto Website which allows bird recordists from all over the world to upload and share their recordings, to the benefit of the rest of us who have ready access to this myriad of bird songs. I encourage all those interested in bird song to visit this site: http://www.xeno-canto.org/.
It was through this site that I was able to contact several recordists, who then allowed me to use a selection from among their recordings on my own website. I have listed these recordings below, along with the recordists.
Paul Driver: Gray-cheeked Thrush http://pjdeye.blogspot.com/
Darrell Peterson: King Rail Kicker Call
Andrew Spencer: Orange-crowned Warbler, Blue Grosbeak, Worm-eating Warbler, Swainson's Warbler, Le Conte's Sparrow, Louisiana Waterthrush, Black Rail, Yellow Rail
Denise Wight: Virginia Rail Kicker Call
Todd Wilson: Brewer's Blackbird http://www.wisconsinbirdsounds.com/