rockm
Spuds Moyogi
Gov.uk, the U.K. government's web presence provides the most straightforward, succinct instructions and requirements for importing bonsai from Japan that I've come across. Wish the USDA/APHIS would take this route. The restrictions/requirements are almost the same...
www.gov.uk

Import bonsai from Japan and Korea to Great Britain
Find out how to import species of bonsai to Great Britain from Japan and Korea, who you can import from, and what the quarantine rules are.