Aloha RichardS,
Thats a whole can of worms. Paul Scheele discusses optimal states of learning in the PhotoReading classes, he and other instructors teach. There are plenty of folk out there selling "meditate like a master" programs that will tell you their take and what their's studies have shown.
Personally, I would just listen to the music provided, or the rickets, ocean, or stream as I do my exercises outside, rather than any entrainment audio. The healing that needs to happen for you at that place, time, and level, may not be at the "ideal" frequency that entrainment program is taking you through at the time.
Another question to pursue is, is it better to entrain the brain into a frequency, or have it work out the natural connections, more biofeedbackish in method? There are some expensive programs out there to do just that.
Much Love, Shawn
