The Library of Alexandria, http://www.bibalex.org/arabic/index.aspx, has a site, http://archive.bibalex.org/mybook/fp/, which provides
electronic books in image format.
These books are downloadable for free. The file format of the downloaded book is .DjVu.
Two sites, FileExt, http://filext.com/detaillist.php? extdetail=djvu, and DjVuLibre, http://djvulibre.djvuzone.org/, both
provide information about this kind of file.
For Windows users, the site LizardTech, http://www.lizardtech.com/, provides a DjVu Browser Plug-in for Windows Internet Explorer.
I downloaded one of the books from the geographical section (Ibn Battuuta), and downloaded the Browser Plug-in from LizardTech. The
system works well.