Wild Horses: An excellent page about the developement of the Mustang.
Military Aircraft Archive: WWII Aircraft: Contains stats and pictures for many WWII aircraft.
Fencer's P-51D Mustang Hangar: Many, Many pictures of the mustang and some other aircraft. Also has some information about the Mustang, but its main feature is pictures.
The Effect of the North American P-51 Mustang on the Air War in Europe: A well written essay about the Mustang's effect on the Air War in Europe.
Art-Haus WWII Aviation: Pictures of Mustangs and other WWII planes.
Miss America Air Racing: Info about Miss American, a famous racing Mustang.
Rolls Royce: Creators of the engine that proved to be the powerhouse behind the Mustang's might.
Confederate Air Force: A group consisting of WWII vets and others who fly and restore WWII era aircraft. In addition to having several Mustangs and Twin Mustangs, they have the only flying B-29 Bomber, FIFI.
Aviation Entusiast Corner: An excellent site about all corners of aviation.
Aviation Home Page: A very excellent site with a virtual plethora of aviation information.
US Military Aircraft: All the information you could ever want about US Military Aircraft.
The Aces List: A massive list of all pilots in all countries that have become aces. Pack a lunch to read through this one ;-)
The Thunder Mustang: The official web site of the Thunder Mustang, a modern Mustang Replica.
The Hangar: A very nice aviation page. Very well set up with a lot of information.
S-51 Mustang: An all metal Mustang Kit.
Tor Erik's Mustang Site: A page with a pretty good Mustang history.
Totavia P51 images: A page containing many, many Mustang pictures.
Mustangs Mustangs.com: An excellent site about both the P-51 Mustang and the Ford Mustang. Well worth a visit from fans of either.
Stallion 51: Ever dream of flying a Mustang? This company offers the chance.