From: http://www.ehow.com/how_5772406_connect-laptop-sony-bravia.html (plus a little bit of my input)
Step 1
Decide whether you will use a VGA or DVI cable. If your laptop has a DVI port, use it as it delivers better graphics than the VGA. If it does not have a DVI port, use the VGA cable. Note that the instructions are the same regardless of what cable you use.
Picture: http://videsignwire.com/wp-content/uploads/2009/07/idt-1.jpg
Step 2
Connect the cable to the laptop’s port, then connect it to the Sony Bravia. The ports for both devices are typically found in the back of the device. Be sure that both ends of the cable are secured to the ports.
Picture: http://www.pantherproducts.co.uk/Articles/images/vgadvi.jpg
Step 3
Change the input display on the Sony Bravia to the input that corresponds to the port you are using. (This is done by pressing “input” on your remote until you get to the right channel.)
Step 4
Set your laptop to display using the DVI or VGA port. Typically, you would press the “Fn” key followed by the key that shows a laptop display on it. This will display the laptop on the Bravia. This key combination normally toggles the laptop’s display among laptop only, laptop and external monitor, and external monitor only. You can also change the settings on the computer by going to “Start,” “Control Panel,” and looking for the display settings. (I believe a Vista notification will pop up on the screen asking you how you want to organize your screen.)
Aaaand, you should be set.