An e-book reader, also called an e-book device or e-reader, is a portable electronic device that is designed primarily for the purpose of reading digital ...

Wherever you want to. Provided you have an e-book reader, and you have got the book on it.

Do not know much about Kindle or Nook e-book but go to the library and see if they have some there for the public to use. Then you can decide which e-book reader works best for you.

on barnesandnoble.com

iPod is not an E-book although it may have an e-reader app such as Kindle.