Nathan,
Sorry you missed out on the disk. When I bought mine, I missed out on a few as well. They are an item that moves pretty quickly, especially if they are in decent shape.
You can always watch ebay in your area. I have mine setup for a hundred mile radius to see what comes up. Usualy its' overpriced or in realy bad shape, but every now and then a deal comes along.
Another good source for deals is
http://www.americanclassifieds.com/index.cfm
Just go to your area. Then do a seach for what you want and include local areas. It will go out a hundred miles and cover all the papers looking for what you put in your search.
Sometimes people list things wrong. Either spelling or under the wrong area. I got my laser level that way. It was in the wrong area on ebay and only had a few bids on it compared to all the other laser levels in the construction area.
Every Thursday morning I check on search for what's come out in the new issue. It takes just a minute and for the few great deals I've come across find it to be worth my time.
To give you an example, I paid $300 for a 5 ft angle iron disk. It has serated disks on fron and smooth on back. It has greese fittings and the angle of the discks are adjustable.
Eddie