Need more volume for entire session

[ajp]

I've recorded a number of songs and when I set up the tracks to record, I had the inputs set so I recorded as high as possible without peaking and then when i bounce to disk, I have the volumes all pretty high, but my final MP3s are not nrealy as loud as other MP3s on my computer. You can take a listen to the tracks I'm tlaking about at
www.westeightfive.com/music.html
and you can hear that you need to turn your volume up to hear them.

So how can I make my final mix louder? Right now I have each track (guitar, drums, vocals, bass) duplicated so I have them in stereo, should I just duplicate the tracks more to get more total voume, or is their a simpler way to increase the final volume of the track?

Thanks.