2GB Memory RAM Upgrade for the Lenovo Thinkpad R61 Series, T60 Series, T61 Series, X60 Series and X61 Series Laptops (DDR2-667, PC2-5300, SODIMM) at Amazon.com
Thinkpad T61 Laptop 2.0 GHz Core 2 Duo 2GB RAM 320GB HDD DVD – Rock Solid!! – ASA College: Florida
Tutorial: How to upgrade ram in a T61 Thinkpad - YouTube