Note that Regia has no control over the following, and neither it nor its member groups are not responsible for their contents:

Anglo-Saxon Calendar (list of months and other information)
Anglo-Saxon Glass in the British Museum (A large range of cups, bowls, etc. in the British Museum)
Anglo-Saxon Names (Names you can use for Anglo-Saxon impressions)
Anglo-Scandinavian Chronicle (essays by Folo Watkins on Living History and Viking Age Reenacting)
Ashmolean Museum (splendid museum associate with Oxford)
British Museum (The home of such items as the Sutton Hoo finds, the Franks casket, many of the Lewis chessmen and many items from the Viking Age)
Colors for your Status (list of modern equivalents for appropriate colors, with notes on the status of individuals using the color)
Coloured Clothes in Medieval Scandinavian Literature and Archaeology (wonderful article by Þor Ewing)
Costs in Early Middle Ages (estimates of what arms, armor and other things were worth
Creating an Authentic Past (A podcast from Colonial Williamsburg that comments on creating reproductions and the difficulty in finding materials. It concentrates on 18C but is of interest to other eras, including our own)
Dark Ages Reenactment Company (Canadian group headed by Darrell Markewitz that among other activities, does reenactments at l’Ans aux Meadows)
Dyes Project (Notes on the Regia Dye Project and what dyestuffs to use for thenty colors!)
Durham Cathedral (impressive Cathedral, parts of which date from early Norman time, where Saints Cuthbert and Bede are buried)
Eating like It’s 999 (Chuck Elshlaeger’s account of eating like an Anglo-Saxon for a year)
Extant Chests and Caskets (A Compendium with illustrations of extant medieval chests)
English–Old Norse Dictionary (from the University of York)

Few Simple Tips for Public Historians Working with Confrontational Visitors (Directed to American reenactors of later erae but very pertinent)

Fornaldarsögur Norðlanda (a listing of Icelandic sagas and their English translations)

Free Digitized Manuscripts Containing Old English h (some manmuscripts from the time not in Old English)

Origin of the term Farb (essay by an ACW renactor on a term that has become ubiquitous in much living history)
Footware of the Middle Ages (Shoes, shoes, shoes, from throughout the middle ages)
Great Pouch Debate (thought-provoking article from a branch of Regia, Gwerin y Gwyr, enumerating period contents of pouches)

The Havamal (the etiquette manual of the Viking Age)
Hedeby (Haithabu) -Schleswig-Holstein regional museum (A number of photos of the reconstructions at the Norse trading center of Hedeby)
Historical Reenactors Guide to Saxon/Viking Textiles (Aidan Campbell talks textiles)
Hurstwic Food Page (Good analysis of Norse diet; the Hurstwic main page, which leads to its many pages, is wonderful!)
Icelandic Saga Database (Sagar in various translations)
Interactive Cathedral Map (not specifically period, but a terrific resource!)
Jorvik Viking Centre (A celebration of the Danelaw!)
Julius Work Calendar (Anglo-Saxon Calendar, also featured in Robert Lacey's The Year 1000 and in The Julius Work Calendar)

Knives from the Viking Age (An illustrated article on knives and shape of knives written by Darrell Markewitz)

Kornbluth Photography (Archives of Genevra Kornbluth, an historian of the luxury arts and photographer)

King Alfred’s Grammar Book (Old English grammar with a glossary, by Michael D. C. Drout)
Labyrinth (Resources for Medieval Studies)

Looking for Evidence (collection of links of extant finds and other historical items for living historians and reenactors)

Mastermyr Find (Excellent book on the tool chest)
Modern English to Old English Vocabulary (What it says. Not exhaustive but very useful)
Norse Costume at a Glance (Quick Overviw by Aidan Campbell)
Norse Months (List of Months and Other Information)
Norse Names (On creating Norse names, including links to names found in Landnámabók)
Northvegr (Asatru site with many primary and other important works)
Old English to Modern Translator (or vice versa; does not have all words you might want but awfully convenient)
Old English Wikipedia (don’t venture there if you have an inadequate sense of humor!)
Old Fashioned Milk Paint Color Chart (a great source for accurate milk paints)
Online Books (mainly Victorian and out of copyright, a rich umbrella that searches Gutenburg, Google Books and many other sources for a variety of books that can be downloaded)
Online Etymology Dictionary (want to know which words came from Old English or Old Norse roots, have fun!)
Onomasticon Anglo-Saxonicum (a scan of the book by William George Searle, first published in 1897 but still one of the sources for Anglo-Saxon names, taken from occurrences in period manuscripts)

Open Domesday (an online digitized reproduction of the invaluable Domesday Book)
ORB (Online reference and primary history))
Online Etymology Dictionary (a very intriguing and habit-forming look at where our modern English terminology came from)
Oseberg Textiles (Article by the co-discoverer of L’Ans aux Meadows on textiles and textile tools found in the Oseberg burial)
Pangur Press (A number of downloads pf books by Walton Rogers)
Regia Home Page (A wonderful collection of articles and pictures, including Authenticity Regs!)
Regia Anglorum–Celebrating 25 Years (shirt video made by Nigel Amos for regia’s silvery anniversary and showing its wide range of interests)
Shields (The Viking shield from archaeology presented by the New Varangian Guard))
Tandy Leather Guide (Leather Thivkness and Weight Chart)
Tents (Compendium by members of Wynmerestow on getelds and geteld construction [with patterns])
Textile FAQ (Valuable compendium by Wynmerestow)
Thoughts on Reenacting (a thought-provoking essay from a later period)
Treasures of the Anglo-Saxons (an hour-long documentary with a look at Anglo-Saxon art and its meaning, with a visit to Wychurst, an appearance by Kim Siddorn and a mention of Regia Anglorum)
Viking Age Compendium (ongoing research into the material culture of Viking Age Britain by the society AO and his wife)

Viking Age Podcast (a number of interesting podcasts on difference aspects of life during the time)
Viking Answer Lady (A collection of articles dealing with many aspects of the Viking Age. Invaluable!)
Viking resources for the Reenactor (The main page for Carolyn Priest-Dorman’s articles on the Viking Age. Invaluable!)
Viking Site (Jesse Byock's web site; he's one of my favorite living historians, and the site delivers)
Weaving and Related Topics (On-Line Digital Archive of Documents)
West Stow Village (a magnificent recreation of Anglo-Saxon life)

Woods Used by Vikings (A compendium of information created by a member of DARC)

Woodwright Shop (online videos from the series hosted by Roy Underhill)

York Archaeological Trust (Top-flight archaeological information site focusing on finds from York, England. This site focuses on photos of artifacts, while this offers pdf downloads of some oop publications)