Notebook and Computer Models manufactured earlier than Fall 2008 are not fully supported by Sony for the Windows 7 Operating System. Some Models have limited Drivers on http://esupport.sony.com. This does not mean its Supported, only that for your convenience, some drivers were provided ( in many cases the key drivers wont be there)
If a specific driver that you are looking for is not provided then you can look to the following options:
1) You can try the driver posted for Windows Vista by running it in compatibility mode in Windows 7. To run a file in compatibility mode, right-click on the installation (.exe) file and select properties. In the properties windows click on the compatibility tab. In the compatibility tab, check the box to run in compatibility mode and select the Windows Vista Operating System that the driver was designed for. Click OK and run the driver installation package.
2) Try using drivers supplied with the Windows 7 operating system. Many Microsoft drivers built into Windows 7 will provide basic functionality for a wide range of devices including Mouse/touchpad, WLAN and Webcams. Please note that generic drivers for these devices may not enable special features for the device, but should still allow general functionality.
A clean install involves installing Windows 7 with no previous operating system present on the unit. When an upgrade from Vista to Windows 7 is performed instead, many of the compatible drivers present in Windows Vista will be transitioned over to Windows 7.
If you have exhausted the above three options and still do not have proper driver/functionality with the said device, unfortunately Sony cannot guarantee full functionality in Windows 7 since the model in question is not fully supported. At that point you can look to third parties drivers. Sony does not guarantee or support drivers from third party manufacturers.