This may be a little out of date, but has some good info. Ignore the 'you suck' part of it, Purge has loads of videos to help people and is also a commentator at DOTA events, so its not derogitory.Cheers, @Theydon Bois. We've started playing against Bots in the office now at lunch to try and figure things out. Seems like a terrifying learning curve given the sheer quantity of characters and I've already learned that I need to read up on them before even considering picking them.
Chose one of the ones Newbee used in the final and a few minutes later was quitting because I just didn't have the understanding let alone the talent to play it.
And, yeah, @Sinzer, a few people have said that since. Going to try and dig out a few of the better earlier rounds and see how they compare.