• Five Chime Consultants - THE air horn dictionary

• The Horn Doc - "Your Rx solution for broken horns and missing parts"

• Locomotive Airhorns - Charlie's Railroad Locomotive Air Horns message board - excellent!

• Horns Inc. - Ed Kaspriske's identity in the horn community

• Horn and Whistle Board - Adam Smith's multi-purpose message board -- a little bit of everything!

• Horn and Whistle Journal - the horn and whistle enthusiasts' group's print journal

• Real Train Horns - Luke's site with beautifully restored and new horns for sale

• Railroad Horns - Matt Donnelly's horn site

• Horn and Whistle Yahoo group

• Train Horns Yahoo group

• Locomotive Horn Signals - so you know what the various sequences of toots actually mean in the railroad world

Whistles

• Western Locomotive Supply - top quality reproductions and custom-built whistles

• MD Whistles - manufacture of reproductions of classic American locomotive whistles

• Horn and Whistle Board - Adam Smith's multi-purpose message board -- a little bit of everything!

• Flue Pipe Acoustics - the physics behind the sound of organ pipes, whistles and flutes

Sirens & Diaphones

• The Gamewell Diaphone Web Site - a site about diaphones

• VictorySiren.com - "The World's Largest & Loudest Sirens . . . EVER!"

• airraidsirens.com - "The Internet's Premier Outdoor Warning Siren Website"

• Horn and Whistle Board - Adam Smith's multi-purpose message board -- a little bit of everything!

Major Manufacturers

• Micro Precision Group - owner of the AirChime and Nathan horn lines

• Airchime Mfg. Co. - older AirChime site

• Leslie Controls Inc. - manufacturers of SuperTyfon horns

• Wabco Locomotive Products - they still catalog and sell the AA-2

• Buell Air Horns - manufacturer of various horns, including a new line of train horns

• Grover Products - manufacturer of truck horns and road-use train horns

• Kahlenberg Brothers Co. - air horn and whistle manufacturers

• Ibuki Horns and Whistles - marine-use horns and whistles

• Dayton-Phoenix Group, Inc. - corporation which bought Prime Manufacturing - they no longer sell, or have information on, Prime's horns