The Metropolitan Museum of Art: Heilbrunn Timeline of Art History outlining carpets from the Islamic World ca. 1600 forward. Carpets in the collection include the Anhalt carpet, the Emperors carpet, the Seley carpet (Herat / modern day Afghanistan), and several Oushak, various mogul carpets and kilims.
Boston Museum of Fine Arts: Lacking some photographs on site, although many important 18th & 19th century Chinese carpets, with many Persian rug fragments of interest.
Hermitage Museum: Pazyryk carpet resides here.
Brooklyn Museum: Gorgeous, early Bergama rugs and garden carpet, several Chi Chi type carpets, and a beautiful garden carpet.
RugRag.com Forum : An educational forum helpful to the beginner to advanced rug enthusiast.
Large Rugs and Carpets: A privately owned website with specialty in oversize and large rug sizes.
The David Collection: Interesting Oriental rug pieces and fragments