I still use SON (www.nabendynamo.de) (Probably much more expensive!)

Some English information about the SON can be found at:
http://www.peterwhitecycles.com/schmidt.asp
Distributor in the US shows SON range of products.
http://www.myra-simon.com/bike/dynotest.html
An older dynamo test article from the CTC magazine.
http://www.vintagebicyclepress.com/VBQgenerator.pdf
A comparison of current hub dynamos.
http://www.audax.uk.net/lights/dyno.htm
A survey of all aspects of dynamo use for long distance touring.