have you tried Calibre freeware? It will convert pdfs to epub, aand others. I have done this with a lot of books. I read them with the iBooks app. ( iphone, not ipod but it should be similar)
Probably won't work on library books because they are drm protected.... but I'll check it out
"Sharing the road means getting along, not getting ahead" - 1994 Washington State Driver's Guide