for the most part it doesn't seem possible; as many laptop CPU's are soldered directly to the motherboard (but it depends on the model), your best bet is to contact Toshiba directly and ask Support if it's possible (or ask in their forums).
In the end, the cost may outweigh the want.
im new to cnet and i think this is about the best place to ask this question because i cant seem to find any hardware spces anywhere else and it seems like everyone is well educated here so heres my question. i was thinking about upgrading my processor, its currently an intel core 2 duo cpu bolth 2.10GHz. a few questions, is that possible? is that very good? and if it is possible, should i also upgrade the ram? (current ram is 4gigs)