Up front I want to make this suggestion first: You could visit your local thrift store and find a cheap tape recorder, buy a box of cheap tapes and do what I'm doing with my ipod for under 15$
Now here is What I do:
Since I have an itouch and my kids have a
old used bought on the cheap... ipod. Is I record it on my itouch and then download it to my itunes, which converts it to a "song" so to speak, then I can upload it to her ipod. The docking station allows it to be played back even in a contiguous loop.
I have recorded bible verses of blessings, School facts she just wasn't getting. And we upload the CD's of memory verses to their ipod and they go to sleep listening to them.
I also downloaded podcasts from storynory and story home (preview them tho they aren't all christian based!!).
Here's some links for you to read

so you get an idea of what we are doing. But mind you I had all this stuff already in the house.
http://support.apple.com/kb/ht2396#
You can use pretty much any ipod to record, as long as you have a microphone. See links below for ideas on what you need
http://www.amazon.com/gp/offer-listing/ ... ition=used
http://www.amazon.com/Mini-Microphone-i ... 376&sr=8-1
http://www.amazon.com/s/?ie=UTF8&keywor ... lfe9wbdk_b
I'm not recommending you run out and buy an MP3 player since
Personally I think a tape recording has fewer steps, and is far cheaper, but since I know how to use the tech and have the equipment this is the route we use. Clear as mud?