There is a lot of sites on the Web offering long
lists of links pertaining to manuscript studies. In order not to copy them
we recommend you just a few of them which are good to start with.
A detailed comprehensive introduction into the topic.
Paleography, codicology, history of manuscripts, bibliographies,
plenty of links to manuscript collections and digitized manuscripts on-line.
Stanford University Library Medieval pages: Manuscripts
A list of on-line manuscript catalogues, library databases,
and collections of digitized manuscripts
A similar list of on-line manuscript catalogues, library
databases, and collections of digitized manuscripts
Georgetown University's site for resources on Medieval
A huge list of various links on the topic.