Is it working and can you feel the hot air coming from the vent port? If the fan has died, it can be replaced and Lenovo does have customer replaceable parts and field replaceable parts to do such depending on how comfortable one is. This requires removal of the keyboard which is usually done by removing 3 to 5 clearly marked screws on the bottom. If the fan is working but just clogged with dust, you can try cleaning the fan with compressed air.
I've had this lenovo thinkpad for about 2 years now and everytime i plug it into the ac adapter the laptop gets ridiculously hot and shuts down. It's especially annoying when I'm writing a paper for school and i forget to save and I lose absolutely everything. What can I do?.. other than buy a mac