I recently published A Short History of the Normans (I.B.Tauris, 2016) and you can find useful links, some of which are included in the book, here. I’ll update this page periodically.
Links to manuscripts
Boulogne Gospels. Boulogne-sur-Mer, Bibliothèque municipale, MS11
Domesday Book. Open Domesday project at Hull
Norman cartularies from Rouen, Archives départmementales de Seine-Maritime
Norman charters from Rouen, Archives départementales de Seine-Maritime
Sacramentarium of Robert of Jumièges. Rouen, Bibliothèque municipale, Ms274
Treatises by Jerome, Augustine and Ambrose. Avranches, Bibliothèque municipale, MS72
Trilingual Psalter from Palermo. London, British Library, Harley MS 5786
Translations of sources online
Anglo-Saxon Chronicle, trans, by Ingram and Giles (1824, 1837). It is better to use the modern printed translations if your library has them.
Extracts from English sources on the Internet Medieval Sourcebook.
Geoffrey Malaterra, Deeds of Count Roger, trans. by Graham Loud, University of Leeds
William of Apulia, Deeds of Robert Guiscard, trans. by Graham Loud, University of Leeds
Other useful links
Battle Conference on Anglo-Norman Studies
Haskins Society devoted to the study of Viking, Anglo-Norman and Angevin history
Mondes normands médiévaux – a research network for Norman history
Norman Connections – a project linking sites in Normandy and south-east England.
The Normans, a European People, hosted by the University of Caen
The Norman Edge project at Lancaster University
Rob Helmerich’s Norman bibliography
Tabularia – online open access journal