Educational links regarding the patch clamp technique
http://sites.sinauer.com/neuroscience5e/animations04.01.html
http://www.cellsalive.com/patch.htm
The Axon guide (Molecular Devices) [attach pdf]
Companies specialized in electrophysiological equipment that also provide support in the electrophysiology unit.
Scientifica
HEKA
Sutter
Dagan
WPI
Harvard Apparatus