Wired has a how-to for rolling your own e-books. The following tools are covered for converting digital files to ePub. This could be quite handy for zapping study materials into e-books.
The tools are:
ePubBud.com - Find out more online in their FAQ.
eCub Cross platform tool
eScape ePub Creator - Converts OpenOffice documents to ePub format.
ODFtoEpub - Converts OpenOffice files to ePub format.
BookGlutton - Converts HTML web pages to ePub format.
EasyEPub - Convert from Adobe InDesign or Quark format to ePub