Manufacturers 

Air Arms	Feinwerkbau	Rohm	Anschutz	Tau Brno
BSA	Daystate	Falcon	Webley	Gamo
Simmons	Crosman	Diana	Umarex	Baikal
RWS	Steyr	Hammerli	Eley-Hawk	Eley Ltd
Aeron	BSA Optics	Cometa	Tasco	Bushnell

Bulletin Boards, etc

AirGunBBS

AirGunForum

Network54

AirGunBoard

PricticalPistolUK

Trajectory Calculators (FREE)