I browsed through here lately and I noticed no one has mentioned a new company on the market that is offering WWI aircraft.

I recently learned of this company during my last IPMS meeting and I was amazed at the detail these kits offered.

The company is called Wingnut Wings and they were founded by none other than Peter Jackson of Lord of the Rings fame

I highly recommend this company as they are high quality, though I would disagree on prices. (but thats the penny pincher in me)

Here is the link
http://www.wingnutwings.com/ww/

Go the the Early Aircraft forum. There you'll find threads since they started releasing kits.

If you are talking 1/32 scale, WNW have released four WW1 aircraft, these are beautiful kits and well worth the expense. They are relaeasing more kits "soon".
Roden also have a pretty good range of 1/32 WW1 aircraft, all very good kits and at a fair price. The latest release from Roden is the DeHavilland DH-2, I've been waiting for this one for a long time.
If the trend towards 1/32 WW1 aircraft keeps growing maybe other manufacturers will follow suit, lets hope so anyway.

Cheers

Des.