http://evilution.co.uk/index.php
And even thought they cover the 450 & 451 they are in gas and can be a tremendous source of info on repairs, PARTS on the other hand will not be as available to, regardless this is a viable info source for we 450 owners.
A second place requiring a look is
http://www.fq101.co.uk/index.asp
In both locations, info can be found for the 450's and some 451s too
Hope it helps
ASM