Got my site at www.requiem.net/folkmonster for a guide on digitising using Cooledit.

Are the old recordings on cassette tapes? if they are, you can often get a good improvement by adjusting the playback head of the deck (take the door off to access the screw head). It's surprising how many portable cassette recorders were used out of alignment and 9 out of 10 tapes I've restored benefit from this.