I can't find a specific document on your exact model laptop. But rule of thumb, for most laptops, the processor is right-side-up under the keyboard. The processor comes out and goes in the same as a desktop processor (lever on side of socket). The first step is to remove the keyboard. I found a site that shows how to remove the keyboard on a Toshiba laptop. There is probably a plastic cover covering the processor under the keyboard. Look through this and tell me if this is enough information to get you going on replacing your processor.
Remember, the processor needs to be the same socket as your current processor, as it is very difficult to locate a motherboard for your laptop.
Here's the link:
Let me know if this works for you.