can i update Mac OS X 10.6.8 to 10.7.0
If your Mac meets these technical requirements for OS X 10.7 Lion, then you can use the Mac App Store tool to purchase, download and install 10.7.
Apple hid Lion when it released Mountain Lion; buying it requires phoning the online Apple Store and ordering a download code for it.
The only Lion version available is 10.7.5, and as Niel said, call 1-800-MY-APPLE to purchase the download code, that will be sent in a few days by email. Cost is $20.
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