The most effective sites are large and very comprehensive.  Instead of my duplicating them, please use the links below; for the most comprehensive info go to the top 2 links under the first heading and the first link under the second heading...

Willys Restoration

www.billys56willys.com
('56 total restoration and how to's)

www.willysamerica.com
(restoration info)

http://www.off-road.com/jeep/willys/
(restoration info)

Willy's general info


http://www.willystech.com/faqs/WillysTruckFAQ.html
(the most comprehensive site i have found, covers restoration, specs, id, etc)

http://mvpimages.net/willys/show.htm
(sister site to above link)

http://www.kaiserwillys.com/
(second only to the above links for willys info)

http://www.public.asu.edu/~grover/willys/
(great source of information)

http://www.willysamerica.com/
(general info, restoration, parts)

http://www.off-road.com/jeep/willys/
(general info, restoration, parts)

http://www.willysonline.com/
(great gallery, forum, etc)