if i use this shield is there still enough power to run a display of some sort to have the song title run across. maybe volume level? http://www.cutedigi.com/arduino-shields/mp3-shield-for-arduino-1.html#googlebase or https://www.sparkfun.com/products/10628
Depends in what you mean by "power"
is there enough space for code, ram, and pinouts to run the mp3 sheild and have a display as well?
Since the shield does all of the decoding, all the Arduino does is send commands over serial. Which you could do with software serial. That leaves tons of resources for you to do other stuff.