Buckets, Pails, & Piggins
The Archaeology of Early Medieval Ireland

How to Make a Coopered Wooden Bucket

Craft Industry and Everyday Life: Wood and Woodworking in Anglo-Scandinavian and Medieval York

These links show buckets used for a variety of purposes. It does not include situlas (buckets made to contain holy water) or washtubs.

See the Portable Antiquities Scheme Finds Database for several finds relating to English buckets, especially iron hardware.