Yes, Apple have a document detailing this - don't have a link sorry.
However, in a nutshell you enable the iPod for disk use, copy the library files onto the device from old pc (this essentially takes the same amount of space as your music), you then drag the original library files from your iPod onto the new computer replacing the blank library on the new pc. If you dont have enough storage remaining on the device for the library data just use an external disk drive instead!
Once the data is in place you then sync you iPod with iTunes on the new computer which blanks the disk and then transfers your data back onto the device.
