Depending on your iPod model, this can or can't be done without iTunes or a similar software. If you can't connect to the Internet using your iPod, there is nothing that you can do to transfer your music. However, if you can browse the Word Wide Web using your iPod, you can try to upload your music from the PC to a cloud storage service like Dropbox and download the music from there to your iPod. There is no other solution to your problem.
