Motorbooks.com  
   Topics include automotive, aircraft, tractors, and bicycles.
   http://www.motorbooks.com

Karen's Books  
   Transportation books including airplanes, automobiles, buses, trains,and trucks.
   http://www.karensbooks.com/

Technical Publications Service  
   Suppliers of manuals for tractors, engines, ATVs, and other maintenance and collectors books on tractors and machinery.
   http://www.tractormanuals.co.uk

Mds Booksales Transport Bookshop  
   Wide selection of transport books and videos.
   http://www.mdsbooks.co.uk/

Beven D Young Automotive Books & Software  
   Automotive, motorcycle, karting books and software
   http://www.bevenyoung.com.au/

Camden Miniature Steam Services  
   Technical books on engineering and transportation.
   http://www.camdenmin.co.uk

Nene Valley Railway Books  
   Transport related publications, both new and secondhand including shipping, railways, canals, aviation, and buses.
   http://www.nenevalley-railwaybooks.co.uk/

RepairManual.com  
   How to carry out routine maintenance, restoration and servicing of cars motorcycles, and boats.
   http://www.repairmanual.com

NADAguides.com  
   Price appraisal guides for used automobiles, classic vehicles, boats, airplanes, motorcycles, snowmobiles and recreational vehicles.
   https://www.nadaguides.com/BuyTradeGuides.asp?wSec=8&wPg=1464