It says I can download music from the computer, but I have no idea where the memory slot is or if I find it will I need to purchase one and put it in.

It's in the battery compartment. Take the battery cover off the back and it should be below the battery. It slides in flat along the inside case.

The K1 uses MicroSD up to 2GB.

If it already has a memory card in it, you don't have to take it out; you can use a MiniUSB cable to connect the phone directly to the computer and copy files over.

If it doesn't have one, make sure you get a MicroSD, they are about the size of a penny.

Pages 26 & 27 of the manual which is online at:
http://www.motorola.com/staticfiles/Supp�/a>