I would imagine that you could put thermal paste on the CPU of most laptops, assuming that you could get the HSF off. I'm not an expert with Vaios, so I couldn't tell you whether you can access the HSF sufficiently/easily, but I think so. Because there is no "cap" on the CPU, I would highly recommend Arctic Ceramique/Alumina. Any non-conductive, non-capacitative paste will work, but those are widely known to be the best.
Also, if you can take apart your laptop somewhat thoroughly (you have my good luck on that), you may find that your laptop has a heatpipe cooler. In that case, I would remove that completely, dissasemble it, purify both sides where the pipe contacts the metal, and apply Arctic Silver 5, being careful not to put too much on so that it oozes out the sides. Then put it back in and use whatever non-conductive/capacitative paste you like to stick it back on to the processor.
Another thing you may be able to do is "teach" your fan. Enter BIOS, and look for an option like, "PC Fan Learning". If there are any other "learning" options, you should probably run them, too. My laptop has options for fan learning and battery learning, and I believe that they are under "PC Health".
Hpoe this helps, and good luck making your fan quieter. I know how it gets on the nerves
Cooler Master HAF 932
Xeon X3370 @ 4.0
4GB OCZ DDR2-1150
Intel X25-M 80GB
WD Black 1TB
EVGA GTX 285 Hydrocopper
Swiftech 1/2" WC system on CPU and GPU