In my world, a firewire cable between two computers enables one of them to look like an extra hard drive on the other. Just like the built in drives.
You open it up and drop the files from one to the other and bob's your uncle. If he is ask him to set it up for you!
ALternative...burn a CD or DVD with all the MP3 files you can fit, take them over to the other computer and drag them into your music folder. Repeat until complete.