Are the sources I list at the bottom of my post not working for you? Or are you looking for something local to Australia or Europe?
The ribbon cable is bog standard ribbon cable for IDC connectors. I use a roll of 40-wire wide cable that I peel off the number of wires I need (eight in the case of the 2x4 IDC connectors I use in that post)
As for the 2x4 IDC connectors, they are a very standard form-factor as well, special only in that they are 2x4 instead of the more common 2x5 or 2x8 sizes. You can use those longer sizes if you want (or even the 2x20 kind used by IDE hard drives), but then you have to be more careful about alignment. :)
Updated:
The Jaycar link that penjuin has for a 2x5 connector will work. Au.farnell.com has an entry for the exact part I use: FCI 71600-308LF, but currently show none in stock local to you.
Marcus, if Little Bird Electronics wanted to get into stocking various kinda weird connectors like these, you should check out 4ucon. They have the 2x8 IDC connector as well as many many others. There lead time is at least a month usually and minimum order quantity is several hundred, but their prices are very good.
Best Answer
Do you mean standard i2c speeds or something specific to picaxes or blinkM?
"The standard clock (SCL) speed for I2C up to 100KHz. Philips do define faster speeds: Fast mode, which is up to 400KHz and High Speed mode which is up to 3.4MHz."
quoted from http://www.robot-electronics.co.uk/htm/using_the_i2c_bus.htm
EDIT: Found this: http://getsatisfaction.com/thingm/topics/picaxe_communication which should give you at least something to test your setup with.