HORIZONS UNLIMITED http://www.horizonsunlimited.com/
The largest online community of overland travellers. HU was started by Grant and Susan Johnson after their epic round the world 11 year trip on a motorbike. There are HU meetings and communities around the world and you can find the answer to most questions on the site or it’s forums.
Their book is “Bearback, the world overland”. A fantastic read. We not only enjoyed reading it but also used it to mark out places we wanted to visit on our travels in the Americas. If you are serious about travelling overland, especially by motorbike, you should read this! http://www.theworldoverland.com/theworldoverland/Welcome.html and on facebook at https://www.facebook.com/BearbackTheworldoverland?fref=ts
ADVENTURE BIKE RIDER (ABR) http://www.adventurebikerider.com/
Events, forum, trip reports, kit – a great resource for overland bikers.