Dan Harden's bodywork seminars page; information regarding what to expect from a seminar and contact form for contacting Dan directly.
Group page for various training group sites around the world
United States groups/locations
Aikido Sangenkai has a great bunch of people training together not to mention the absolute goldmine of translations provided by Chris Li in his blog; any person serious in investigating aiki and internal arts should check out the articles here!
Training with the Central PA and Eastern Shore MD group
Sangenkai groups in Bristol and London. Bristol group is run by Rich and London group by Lindon. Big recommendation to get in touch with these amazing guys if you're close to either city in UK!
Ben and Kari are both highly experienced in the material and great to train with, get in touch with them if you are going to be in the area and are interested in meeting up to train.
Sangenkai Germany has study groups in Darmstadt and Manheim.
Kristoffer and Matei are first class martial artists and great people to boot; if you're in the vicinity of Oslo I can't recommend enough getting in touch with them to train.
The Spanish group are a great group to train with and you'll find a number of dedicated practitioners from several martial arts who are putting in serious work on the material; they're also lovely people who enjoy good fun, food and drinks outside of training.