Possible to Overclock Intel Core 2 Duo TM6400?

I have this processor in a Dell Inspiron 1525. I'm very new to overclocking and I'd like to know if its possible + the best information/links on how to do it properly.

It's definitely possible, yet I would not recommend it - laptops aren't platforms that really handle increased heating and power draw that well. That being said, if your bios does not support OCing, you could perhaps look at some tools like the older SetFSB, might be able to do something for you. But again - I highly advise you don't try.