A1304 Logic Board (1.86GHz C2D, 2GB RAM) for Apple MacBook Air 13 inch (Late 2008, Mid 2009)
A-Tech for Apple 6GB Kit (1x2GB + 1x4GB) DDR2 667MHz PC2-5300 200-pin SODIMM for MacBook (Late 2007, Early 2008, Early 2009), MacBook Pro (Mid 2007, Early 2008), iMac (Mid 2007) - Memory RAM Upgrade at Amazon.com
OFFTEK 4GB Replacement Memory RAM Upgrade for Apple MacBook Pro 2.26GHz Intel Core 2 Duo - (13-inch) (DDR3) (MB990LL/A - Mid-2009) (DDR3-8500) Laptop Memory at Amazon.com
Review Apple MacBook Pro 15 Mid 2009 2.8 GHz - NotebookCheck.net Reviews
Macbook Air 13" (13/14) with SSD VS Macbook Pro mid 2009 - Is it faster | MacRumors Forums
MacBook Pro 5,5 (Unibody 13-inch, Mid 2009) 2.26 | 2.53GHz
MacBook Pro: How to remove or install memory - Apple Support