I really like these two sites, which sell either plans or kits for very small structures.
Tumbleweed Houses – www.tumbleweedhouses.com/
Modern-Shed – www.modern-shed.com/
Tumbleweed Tiny House Company
“…since 1997 I have been living in a house smaller than some people’s closets. I call the first of my little hand built houses Tumbleweed. My decision to inhabit just 89 square feet arose from some concerns I had about the impact a larger house would have on the environment, and because I do not want to maintain a lot of unused or unusable space. My houses have met all of my domestic needs without demanding much in return. The simple, slower lifestyle my homes have afforded is a luxury for which I am continually grateful.”
Houses
-Z-Glass house
-XS house
The blog is pretty interesting and informative. There are posts about reclaiming furnishings from old RV’s, off-grid power stations to store and distribute energy, and off-grid uses of wind power to generate residential power.
The Modern Shed
“Modern Shed is simply about storage, fun, space, architecture and your back yard. It gives you the chance to have an office away from home, a small art studio, or free up room in the garage. Stop paying offsite storage and increase the value of your home and quality of life.”