Hi Thomas,
Not sure what scale you have in mind, but you could try this guy in the UK:
http://www.thefusilier.netHe specialises in World War 1, and his figures are excellent.
Andrea Miniatures also do a series of WWI figures, though personally I'm not too keen on them (mostly very static, and with oddly-sculpted faces).
Hope this is a start for you.
- Steve