Well, I pulled the trigger on one of the Supermicro 4U servers available on ebay currently, but got them without the trays. TAMS ships the servers in a strong box with excellent foam packaging. Got about 30 new trays off of ebay and newegg to finish it off with some spares.
Would like to thank the OP for making this public.
Now the time is coming to build it up and mod it a bit. I already have quiet Nexxus 80mm fans that I had from another project, so I will swap those in. Got a Corsair 850w PSU from newegg, 16Gb (4x4Gb) from ebay seller (turned out to be Kingston), and a pair of the 4219EE processors from Amazon (a no brainer upgrade at about $10 each even if I do end up doing software RAID). I need to get a couple HSF's for them. Also have a couple of 80G Intel SSD's for OS and possibly ZIL cache (not sure if I will do a ZFS flavor or WIndows/Flexraid).
I did try to order some replacement hard drive controllers, but did not do my homework sufficiently. I ended up ordering a couple 3ware 9550sx-12 controllers off ebay but they don't seem to support >2Tb drives ... a no go for me. So I will see what I can do with the stock hardware. I'm still not 100% positive the stock controllers will work with >2Tb drives, but we will see.
Then I have to start buying drives ... I have a few drives, including a 3Tb, that I can test with in the meantime.
Then ... to ultimately put it to use storing music and movies via ReQuest (which I also don't have yet ... but soon