If you don't take the time to do this you're really selling yourself short. Look at how many post there are here asking what the band is called. You need to get some cover art and tag those mp3 properly, anything else looks unprofessional. It's such a small amount of work in comparison to the amount of work you've already done. You never know who's listening!
Please take my comments as they are intended. If I didn't think the product was any good I wouldn't have bothered to make them.