Hi can someone give me a part number or description for the socket needed to make a cable connection to the 26 pin Pi i/o? Thanks 
How about SOCKET, IDC, CLASS 3, 26WAYSOCKET, IDC, CLASS 3, 26WAY that's just one example, there are plenty of variations on the theme.
Thanks its Farnell pt no 3815730
Oh, that's odd.. I thought the farnell part number was in the pop-up window, but seems it's not. Sorry for making that more difficult than it needed to be.
If you don't need access to all the pins a nice connector is the AMP MTA100 series (as an example Farnell 3-640442-2). If you only need some pins on a single row this connector will fit. It's a little expensive for the special crimper but the connectors are very low cost, you can get them for different gauge wires, and you don't have to strip the wires or do any prep.