M.W.
Hi J.,
I bought Soothing Sounds for Sleep from Amazon.com:
http://www.amazon.com/Soothing-Sounds-Sleep-Hush-Little/d...
I thought it was great! This CD got us through long car rides with a sleeping baby. Ironically he liked "Highway Hum" the best (I guess the real thing wasn't good enough).
And we would play the vacuum cleaner track all night. The only trouble is that the volume decreases at the end of the track so when it repeats, there are a few seconds of silence. Other than that, it was a sanity saver. :) We used it for months.
OK, I hope that helps! Good luck!