Disc cover from wheelbuilder.com

Try to call or e-mail them.  They were usually reasonably prompt with responses for me.

I have one.  (In fact, it's still on my bike, b/c I've been too lazy to pull it off from the race the weekend before last.)  I've been very pleased with it.  Takes ~20min to install once you've done it a few times.

Echo the previous post -- just give them a call.  They were great to work with.  Mostly they are looking for info on the rim depth.  I think are are measurement instructions on the wheelbuilder website;  but, you can also look online for the Ritchey website (or someplace else with the wheel dimensions). 

Thanks for the motivation...ordered mine today for my power tap wheel...should have done it earlier so I'd have it for practice for my race Saturday....next race.

Now to get a cool, sexy front wheel...hmmm. 

The reason they want to know your exact wheel measurements is because they need the diameter of the current rim section.  This tells them what diameter bolt circle is required so that the screw connectors don't interfere with the rim.  Also the spoking pattern (number of spokes) so that the spacing of the connectors doesn't happen to hit right on a spoke.  Then they need the hub brand, because of the central cut out.  I bought a pair but have not ridden on them yet.

NO, they don't make the same sound, but ARE as fast as a "real" disc. I ordered mine uncut and got reprimanded for it by the guy who emailed me back. My excuse was that I am poor and the $75 was enough of a stretch for me.

 I cut it myself and it looks awesome.

I agree, Aaron.  I got the cover installed, I was surprised how much I noticed the weight when I just picked up my bike.  Just holding the covers themselves before installing didn't seem as heavy.  weird.  (I don't know that it made any difference on the race course, though.  The old 'aero trumps weight' argument.)

Someday I'll upgrade to a real disk.  In the meantime, I'll just try to offset that disk cover by losing 1/2 pound of my weight. (Which also makes me more aero too, right? )

Subtle but distinct difference (for weight weenies) is that your body weight is NOT rotational weight, as is your wheel, so you may have to lose a full pound or two to offset the weight of the wheel cover.

Of course the "cost" of that added weight is nearly zero.  But I know you're not a weight weenie Bear. 

I "lugged" mine up one of the hilliest half iron courses around a couple weeks ago and will do so without hesitation at IMLP as well.

Do you just remove the cassette, and undo the screws when you want to take it off / put it on?