eBay. I got 6x4GB brand new sticks pulled straight from a server for under $100 shipped. They are ECC as well.
See above post. I'm not throwing out arbitrary numbers. I actually bought some less than two weeks ago for my Mac Pro.
Sorry, no way were those new AND Apple certified with heat sinks.
Sure, you can use RAM without proper heat sinks ripped from a server, but why would you want to?