Click on the Vendor name at the left to view their information. Each page loaded into this window will contain the following:
 
Vendor Name, Location (location links to the appropriate map)
 
General Goods: A summarized list of the general items they sell
 
Specialty Goods: A list of specialty items such as Musical Instruments, Gadgets, Spellbooks, or Quest related items
  
Unique Items: A list of any items unique to this vendor (any item already listed in Specialty Goods will not appear here)
 
Additional Information: Any information unique to the Vendor.