Apple iPod Nano Official Site
You can read many details and information about iPod Nano in their manufacturer site. Details like complete features, technical specification and etc.
www.apple.com/ipodnano

iPod Nano on Wikipedia
In this wikipedia, you can browse the complete list of iPod Nano products.
http://en.wikipedia.org/wiki/IPod_Nano

Gadget Just 4 U
GadgetJust4U.com provides information about popular  gadget and technology news. Be sure to visit if you are a gadget mania
www.gadgetjust4u.com