For a computer wallpaper, there are a number of sites that offer them for free. One such site is Fan Pop. They are available for download at these sites.
Alex Russo from a popular Disney Channel show is very much alike Harry Potter by her characteristics and story line.
Mr Ollivander
One can purchase a Harry Potter Sorting Hat from various websites like Amazon or eBay. Both websites offer a great amount of products, including a Harry Potter Sorting Hat.
Yes you can purchase Harry Potter and the Sorcerer's Stone in both paperback and hardback.
Harry Potter clothing can mainly be purchased on the internet. There are many places to do so such as buying Harry Potter clothes on eBay. You can even buy Harry Potter clothing at the WB Studio tour in London.
There are lots of places where someone can purchase Harry Potter posters. Some of these places include; Walmart, Target, Best Buy, Michaels, Amazon, and eBay.
You can do a search on Google Images (image.google.com), for "Harry Potter wallpaper". As far as I know, most wallpapers are available for free - no need to actually pay anything. This may be related to the fact that they are often used for promotional purposes. In any case, before actually paying, you might want to search a bit more, whether you can find the same wallpaper for free.
Harry Potter audio books are not very challenging to find. Any retail store that sells books will likely sell Harry Potter audio books. Barnes & Noble sells Harry Potter audio books.
Flourish and Blotts was the name of the bookstore.
You cannot legally download the Harry Potter video games. You can purchase them and use the disc to play the game.
Harry Potter and the Philosopher's Stone is still available to purchase. In some countries, the title was changed to Harry Potter and the Sorcerer's Stone and the former title is unavailable.
Someone looking to purchase Harry Potter action figures can look in many places. Toys R Us and Walmart may have these figures. Websites such as eBay and Amazon will more than likely have listings for Harry Potter figures as well.