I just wrote this to a friend last night and think you might find it useful! :)
I just met with my DJ (George) and I had to share (http://cedjs.homestead.com/) It's the one that my wedding lady recommended -- he sounds really awesome. He has all his stuff online (even payment if you want) -- you can search all his songs and makes play- (and do not play) lists all via your account on his website plus all this other cool stuff. You designate which songs are for the cocktail hour, dinner, recepetion, etc and for each indivdiual song if you want you can even write note (i.e. dedicate this to so and so)...
Also, it's all wireless so if someone requests a song he doesn't have he downloads it immediately at the wedding. Anyway, since DJ stuff is so stressful I figured I'd send my review! Tell him Katie and Steve sent ya :)
Seriously, the BEST band I have ever heard: high school, during and after college. They are AMAZING. They come with their own DJ. Now if you only want a DJ - USE THEIRS. You can definitely book him separately. During the break between sets, the DJ kept the dancing alive the entire break - people danced continuously throughout the night. Time Flew, people raved...HIGH RECOMMENDATION.
They all graduated from the Berkeley School of Music - All in the mid 20s and very professional and talented.
We didn't request anything songs except for the father/bride, mother/groom and 1st dance songs. They contributed everything else - AND were AMAZING.