Shaun,

There are a lot of tools out there that will automate it for you but they usually do it for a specific tab (netbet pro for example) or specific bookmaker.

I wrote my own code that just uses the standard HTTP posts to place the bets. Its not hard if you understand how to code already. But if you don't know how to code then there is probably a steep learning curve.

Oh I use the Betfair API as well.

Good Luck