Centre Nationale du Costume — In French, images of theater costumes, listed by time period. Includes bios of the costumers. Tres cool!
Costume Classroom — Online costuming courses, some are offered all year. Classes taught by Lea Dread, Jennie Chancey, Marna Jean Davis, Nicole Kipar, Juanita Leisch, JP Ryan, and more.
Costume Design Page — Costume construction tips ~or~ "Everything you ever wanted to know about costume construction and wish someone had told you ten years ago, dammit."
Costume Gallery — Over 25,000 images of costume online. You must purchase a "Library" membership to view all of their documents and images.
Costume History Links — This page, titled "Costume History," has links to many articles.
Fabric Glossary — List of fabric terms from Medieval through mid-20th century.
Historical Clothing — From website: "A bibliography of sources for the design and construction of clothing throughout history."
Internet Centre for Canadian Fashion & Design — This site is a directory for Canadian fashion designers, schools, etc. But it also has a nice Textile Dictionary and Fashion Glossary.
Northern Society of Costume & Textiles — A group in UK that "was founded ... to encourage the study and preservation of costume and textiles." They sell patterns made from original clothing, including a dress that belonged to Charlotte Bronte.
Quickie Textile Guide — Handy-dandy guide to determining the fiber content of textiles.
Rit Dye - Dyeing Techniques — Rit's site lists not only all their colors, but also how to mix them to create custom colors.
Sew-Whats-New.com — General sewing site that has articles, sewing lessons, book reviews and more.
Textile Reference Manual — Describes the different kinds of textiles and their properties. Also links to articles about textiles.
Threads Magazine — Lots of good articles on sewing, including basics, garment construction, etc.
Visual Dictionary of Fashion — From Kent State University. All kinds of information on fashion from the 18th through 20th century. Lots of good stuff here!
Weaving, Lace and Related Topics — A site with documents on weaving, lace, etc. Includes the "On-Line Digital Archive of Documents on Weaving and Related Topics" — books, manuscripts, illustrations and more.
— From the Canadian Museum of Civilization, a list of books about millinery.
— In French, images of theater costumes, listed by time period. Includes bios of the costumers. Tres cool!