I ordered mine from MCM electronics. It arrived in a week. I LOVE this thing. I even built the LEGO case for it, based on plans you can download from the Raspberry Pi support site.
I also got mine via MCM, they only had the bundled ones (stand-alone Pis were back-ordered). Worth it, with Linux on a SD, plus a case and power supply. I run Debian on one of my home servers, so this should be pretty easy to get up-to-speed on.