I recently received DotA 2 as a gift from a friend. It was very generous of him, but I have absolutely no idea what I'm doing. It seems like it is even harder than Team Fortress 2 (which is actually very simple once you get the hang of it). This similar question does not seem to answer the question.
Welcome to Dota, you suck. This aptly titled guide is by far the best for new players to learn Dota2. It's all-encompassing and should have everything you need to get started, but feel free to follow up with additional questions if anything seems confusing.
Here is another great all-purpose guide. It's a little newer so it's not as finely tuned, but it's incredibly detailed and very thorough.
You should also check out Dota 2 Alt-Tab Guides for basic item builds and skillbuilds. I've personally written a majority of the guides on the site and will vouch for their effectiveness.
Good luck. =)
Apart from Purge's Welcome to Dota 2, you suck guide: http://www.purgegamers.com/welcome-to-dota-you-suck
there are also a couple of tutorials on youtube, search for "dota2 tutorials". here is a 5 min start vid:
here is a 45min vid:
And try to watch some vid of people playing. TotalBiscuit has about 10 Dota2 videos so far, that got me started,this is the first afaik:
A decent way to start is to pick one or two heroes and "focus" on them. Get to learn the game, last hitting etc. You can start with creating your own game with just bots. This will give you some good learning and no "yelling" from other players. I just follow the items guides the games give you.
Then when you feel like you know the basics, start playing Co-op games of 5 players vs 5 bots. Expand the list of heroes you feel good with (start by watching a vid of them being played helps a lot).
And after a few co-op games start playing some real games, enjoy the game and don't be discouraged by players yelling at you.
basically its really simple to start playing dota 2, best moves that you can do is play a lot of games vs bots so you can learns items, heroes, map. Than you can start watching a lot of different streams, for example you can use WePlay dota 2 stream or just find any stream on twitch. Also best idea to look at pros that playing dota on tournaments like starladder, same WePlay league ooooor the international that will be pretty soon enough =) gl in your starts =)