Here's a selction of useful links not associated with any location in particular.
Border Crossings
Buddhist Studies at UofT
Database for Buddhist Cave Temples in China
Digital Silk Road
International Dunhuang Project
Islam in China
Royal Ontario Museum
Scripts
Silk Road Seattle
Silk Road Seattle - Silk Road Geography
Silkroad Foundation
Studying Religion at UofT
The New Dominion (news from Xinjiang)
UNESCO World Heritage Sites