Big Big Love: A Sourcebook on Sex for People of Size and Those Who Love Them by Hanne Blank, published by Greenery Press [Buy]
A great resource on practical tips for having sex as or with a larger sized partner — e.g. pragmatic stuff like how to perform oral sex on a partner with huge thighs
ISBN 1890159166

Body Positive
Boosting body image at any weight.
http://www.bodypositive.com/

Nomy Lamm
“badass fatass jew dyke amputee” – see her site for information on “Phat Camp” for adults and young adults.
http://www.nomylamm.com/