OWC / Other World Computing 4GB 1333MHz 240-Pin SDRAM DIMM DDR3 (PC10600) Memory Upgrade Module for Mac Pro 'Nehalem' & 'Westmere' Models, PC Desktops - Walmart.com
Amazon.com: OWC 16GB (2 X 8GB) DDR3 1333MHz 240-pin DIMM ECC Memory Compatible with Mac Pro 2009-2012 'Nehalem' & 'Westmere' Models (OWC1333D3W8M16K) : Everything Else
OWC 32.0GB (2X 16GB) PC10600 DDR3 ECC-R 1333MHz 240 Pin Memory Upgrade Compatible with Select 2009-2012 Mac Pro Models (OWC1333D3X9M032) at Amazon.com
8.0GB OWC Memory Upgrade Kit For Early 2008 Apple Mac Pro
OWC Offers 16GB RAM Upgrade for New Mac Mini, For $1400 - MacRumors
8GB Memory Upgrade for MacBook Pro, iMac, and Mac mini