@shadow71 If only it was that easy. The drivers are not there, just as the OP stated.
However, VPCZ136GG is listed on "Applicable models" list on these "VPCZ13 Series" pages:
Original Drivers and Utilities for VPCZ13 Series (Windows 7 64Bit)http://www.sony.co.in/support/download/419646
Windows 7 32-Bit Downgrade Drivers and Utilities for VPCZ13 serieshttp://www.sony.co.in/support/download/417867
[rant]What use is of the fancy website, if it can't provide the one thing users go there for...[/rant]