I can't install my all in one Lexmark x75, I can't find the CD installer.

You should be able to download the driver directly from Lexmark's website.

Here is a link that might be what you need. (http://downloads.lexmark.com/cgi-perl/downloads.cgi?lxkprod=Lexmark+X75+PrinTrio)

Hope this helps,
WallyH