Wikipedia
Everything you need to know about the history of ballooning is on Wikipedia.
Bart’s Special Shape Balloons
A ballooning enthusiasts site which features images of a number of special shape balloons from around the world.
CAA (Civil Aviation Authority)
The CAA is the regulatory authority for hot air balloons in the UK. They have all the information with regards to licence application and balloon safety.
BRITISH ASSOCIATION of BALLOON OPERATORS (BABO)
Trade organisation representing holders of UK hot air balloon Air Operator Certificates, looking after the interests of passenger balloon ride operators both within the UK, and internationally.
BRITISH BALLOON AND AIRSHIP CLUB
Promotes the discipline of lighter-than-air flight comprising hot air ballooning, gas ballooning, and airship flying. Also organises and promotes competitive and international ballooning.