If you are around capital markets for long enough you'll get either first-hand experience of algo trading or you'll get to meet some of the folks who work on it.
From nothing more than a 2 minute inspection on the course of sales data (available through any reasonable broker platform) you can see a bot is in operation and the noticeable regularity of the trades. If you have the ability to copy/past course of sales into Excel or other package you will see what I am talking about.
For an overview of the algo world, an insight into the strategies employed and developments in the industry, I can recommend the excellent 'Automated Trader' industry magazine available in print and online versions here:
http://www.automatedtrader.net/
A lot of the complex strategies used in the industry are not disclosed for commercial reasons but you'll quickly get a gist of the simple ones - one of which is in operation today.
Subscription is very pricey but you can probably get a 2-3 month trial if you can demonstrate you work in the capital markets. I believe they are UK based.
Even if you are still a non-believer and think this is all la-la land just sit back and watch what is happening. It's not rocket science.
CER Price at posting:
20.0¢ Sentiment: Buy Disclosure: Held