I haven't listened to the cds on the site you list, but I do know from experience that certain types of sounds/rhythms will propel you into a meditative state quickly.
I have a fairly old light and sound machine, think the brand name is Nova, that I picked up from Tools for Wellness. I'm sure new models are even better. I originally got it to help with migraines, and it does help (doesn't alleviate them though)--but it's also very good for reaching alpha, theta, and delta states quickly.
The bonus? Once you are in those states a number of times, you come to recognize what they feel like. Once that happens, you can be anywhere, close your eyes, and attain one of these states. So I don't really use mine as much these days, because I can do it without it.
