How Many Songs can 512 Mb Hold?

That truly depends on the bit rate, quality, and compression of the song. For instance, a MIDI, which is what old Nintendo games used to create music, is very very tiny, and would only take a second or two to download on a dial up modem. An MP3, however, would take nearly half an hour on a dial up modem. The best way to find out the size of your songs, is to right click on them, and hit properties.