Will computers running Windows 7 still be available for purchase after the release of Windows 8?

probably,because as you can see some computers running windows xp,and vista can still be bought and windows 7 has been released for like 3 years.so most likely.right now most retailers are making a deal such as "if you buy a windows 7 laptop you have the option to upgrade to windows 8 for 14.99" or something along those lines.and itll probably stay that way as most people don't like windows 8,I myself as a person who uses the computer for video editing and 3d modeling purposes do not like windows 8's limited interface,with all of it's restrictions and it's mobile os feel.I doubt manufacturers would want to hurt their sales by promoting windows 8 despite microsofts encouragement.so itll likely remain for around 5 years if not more,and most likely more.

Most likely, yes. Windows 8 is going to flop like windows vista and ME, so 7 will be available for longer

of course, windows 7 will last for years in the future

and if you want windows 7 or windows 8 , you can get it on www.getsoftwarekey.com

More than likely, yes.

I remember Vista computers still being around for awhile when 7 came out so I would not worry about it.

Until they're all sold, yes.