For the past two months, I have been playing with my Nook Simple Touch. It is sold in the United States by Barnes & Noble. For product specifications, follow this link.
The light weight unit makes it easy to hold for extended reading sessions. The e ink technology is easy on the eye and accomodates reading from any angle, including laying down.
I have found it very easy to access wifi and shop directly from the unit. Once you have set up your account, it is simple to select and purchase a book. Note, that at present only Americans can purchase ebooks from B & N. However, if you register your Nook with an American shipping and billing address, you can purchase books from most anywhere in the world. Since I am in Canada, I have registered mine to a cousin's address. It works perfectly. Books are immediately available to download. I can also browse B & N using my laptop and add books to my library for later downloading.
It is also easy to purchase books for other sources. To do this, you need to install Adobe Digital Editions (a free software package) . After purchasing your book, download it to this software following the vendor's directions. Next, plug your Nook into your computer. It should show up as a 'shelf' in ADE. From there, it is simple to drag and drop books onto your Nook shelf. I have Windows 7 on my computer and it does not work. Windows 7 views the Nook as a device that needs drivers. ADE wants to treat the Nook as a removable storage drive. To download books, I have to go to my ancient desktop where everything works as it should, just slower.
I have used B & N's online help. There are lots of answers to common questions. If you are having difficulty, that is the first place to look. If you need further assistance, scroll further down the help page and look for the 'Need Help, Chat Now' logo and click there. Depending on the time, you can message directly with a knowledgable technician. I have done this twice. While they weren't able to help with the Windows 7 issue, they did help me connect with my old desktop.
Further information about the Nooks, can be found on the B & N Nook blog. From the blog you can also access the forums/discussion boards, look to the right near the top of the page for the 'Choose a Discussion' drop down menu. I have been there several times searching for help and have found some very knowledgable users who have been most helpful.
One feature I really like is that I can define my own shelves. To do this, go to the library screen, in the left hand menu, select 'Shelves'. On the right of the screen is a button that says 'Add Shelf'. Select that, name your self and then 'enter'. Next will show a list of all your books with a check box. Use your finger to select each book that you want to move to that shelf . When you are finished adding books to your shelf, 'save'. This is a great feature if more than one person is using the Nook.
One feature you won't want to miss is Free Fridays. Each Friday, B & N offers one complete title for free. From your Nook reader, go to the Shop page. the bottom half of the screen shows the current advertisements. On Fridays, one of them will be the offer of a free book. Select it to get a description of the book, and then decide whether you want to purchase it for free.
Storage. I currently have about 85 books with space for 10-15 more. A micro SD card to a maximum size of 32GB can be purchased. 1GB allows for the storage of approximately 1000 books.
Daughter has been using the Nook more than I. She finds it very easy to use and great for on the school bus.