im with John on this, PDAs are excellent... i was pleasantly suprised
at the quality of the onboard mic when the recording type is increased
to 16bit.

something like resco recorder http://www.resco-net.com/audiorec.asp
works well - as you can adjust the gain. you can save direct to SD
cards also which can be easily transported to a PC for any editing
work.

cheers

Luke