Archers & Archery
Toxophilus - The School Of Shooting

The Great Warbow: From Hastings to the Mary Rose

Secrets of the English War Bow

The Medieval Archer

Longbow: A Social and Military History

The Crooked Stick: A History of the Longbow

Bowmen of England

English Longbowman 1330-1515

The Book of the Crossbow: With an Additional Section on Catapults and Other Siege Engines

The Crossbow: Its Military and Sporting History, Construction and Use

How archers would have dressed (or armored) in the Middle Ages, in terms of realistic period portrayals of archers. This list should also be useful for viewing period depictions of archery accoutrements.

There are plenty of unrealistic examples, of course; this list avoids figures dressed more for allegory or myth than for practical archery.

See Archers in Action for a brief but interesting description of medieval combat archery, or these links on medieval archery equipment.

Also notable are portraits by Memling and van der Weyden of men holding arrows. There is an interesting description of medieval Welsh archers at Data Wales.