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

Shaun if you can handle Excel Betting Assistant includes an interface to Excel to enable you to analyse prices and place bets using triggers from an Excel spreadsheet.Betting Assistant is free to use for 30 days after which you will need to subscribe if you wish to continue using the software.
Subscription is around $12 per month.

Betting Assistant has just introduced conditional bet placement without the need for excel.
So for example you rate a horse even money, if the price hits $2.20 or more you can have Betting Assistant place the bet for you, if the price is $1.80 or lower it can lay the horse for you.
Brilliant, this is the best software, best development and best support for a very reasonable price.

If it uses betfair i can't use it as i am in WA

Hi Shaun,
Isn't it amazing how these TAB agencies operate?
You can't bet on Betfair in WA, and I just opened an account on TabOnline, the Queensland TAB, but they have such a rigorous requirement for the 100 point banking proof, that I nearly didn't make it. The reason being, that you have to be known to the referee for 12 months or more.
Having just moved about 250K from my old place, where I was known to all, maybe more than I wanted? LOL, I found it hard to get someone to sign the freeking papers.
I had no such problems with Betfair, just go to a Post office and present a few docs. and it's done electronically.
Good luck