http://www.6moons.com/audioreviews/zigmahornet/zigmahornet.html
http://www.diyaudio.com/forums/full-range/139493-zigmahornet-family-project-if-you-cant-beatem-joinem.html
http://www.enjoythemusic.com/diy/1109/merrill_dca_4.htm
The second link should have plans. These are loved by all because they are so easy. The Jordan driver used by 47 labs is just a modded jx series driver. The 92s is new but should all be the same. Not cheap though.
If I were building these as a beginner, I might be inclined to start with cheap 4" drivers from Fostex or similar. Once you are blown away by that quality, then upgrade drivers.
I'll try to upload my office system today or tomorrow so you can see what I'm playing with...