Upgrading to Mountain Lion
You can upgrade to Mountain Lion from Lion or directly from Snow Leopard. Mountain Lion can be downloaded from the Mac App Store for $19.99. To access the App Store you must have Snow Leopard 10.6.6 or later installed.
If you need to purchase Snow Leopard contact Customer Service: Contacting Apple for support and service. The price is $29.00 plus tax. You will receive physical media - DVD - by mail.
Third-party sources for Snow Leopard are:
Snow Leopard from Amazon.com
Snow Leopard from eBay
After you install Snow Leopard you will have to download and install the Mac OS X 10.6.8 Update Combo v1.1 to update Snow Leopard to 10.6.8 and give you access to the App Store.
If you need to purchase Lion contact Customer Service: Contacting Apple for support and service. The cost is $19.99 (as it was before) plus tax. It's a download.
Be sure your computer meets the minimum requirements:
Apple - OS X Mountain Lion - Read the technical specifications.
Macs that can be upgraded to OS X Mountain Lion
- iMac (Mid 2007 or newer)
- MacBook (Late 2008 Aluminum, or Early 2009 or newer)
- MacBook Pro (Mid/Late 2007 or newer)
- MacBook Air (Late 2008 or newer)
- Mac mini (Early 2009 or newer)
- Mac Pro (Early 2008 or newer)
- Xserve (Early 2009)
Are my applications compatible?
See App Compatibility Table - RoaringApps - App compatibility and feature support for OS X & iOS.
For a complete How-To introduction from Apple see Apple - Upgrade your Mac to OS X Mountain Lion.