Here is a link to a page which has a lot of info on building your own cables.

http://www.planetfall.com/~jeff/obdii/

Looks like a neat home project for anone who is handy with a soldering iron. Wonder if it works with the Fabia?

It will work, except that you may have to preset the baud rate for the engine ECU, at least you do for the 1.4 16V engine.

By the time you have bought the parts and connectors you can buy a ready made unit so cheaply it's hardly worth the bother to make one these days. .

Try:

http://www.ecufix.com/shop/