do shell script "osascript -e 'version of application "Application"'"
Code:do shell script "osascript -e 'version of application "Application"'"
Something to this affect should work. You need to tweak the quotation marks obviously. Replace "Application" with the app you want to find the version.
version of application "Application"
I don't know much about AppleScript, but why escape from AppleScript into the shell just to enter AppleScript again.
Is the above not the equivalent of:
Code:version of application "Application"