From Airliners.net. I've taken an interest in WW1 aircraft and I thought these shots were interesting. The first one makes an excellent desktop background.
Sopwith Tripehound
http://www.airliners.net/open.file/414070/M/
Sopwith Pup Cockpit. Not much in instumentation back then.
http://www.airliners.net/open.file/354388/M
Two Fokker DR1s in formation.
http://www.airliners.net/open.file/351017/M/
Vickers Vimy Replica. Not really a WW1 plane but an interesting example of early bombers.
http://www.airliners.net/open.file/142439/M/
Bristol F.2B, one of the world's first inline engine fighters.
http://www.airliners.net/open.file/278567/M/