If I get some time I'll try to put some information together on this. It's really awesome that more and more people are wanting to stream their tournament matches so this could be very useful.
Here's an outline of all of the references I want to give for this:
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Video recording softwareCamStudio (for Windows, I don't know of any free recording software for Linux)
video tutorial Don't worry about codecs, it will almost certainly work right away
Gives you a lot of flexibility on audio inputs and such
Will likely not require any editing for most of your video recording needs
Streaming softwareOpen Broadcasting Software (OBS) You can also use this to save videos instead of (or in addition to) streaming them if you want
OBS text tutorial for Windows OBS text tutorial for Linux OBS video tutorial for Windows I've never had trouble with my stream key like this guy has
The only setting you should use that isn't what Twitch prefers is to uncheck "Use CBR" -- if not you're going to get terrible lag on lots of things, including Goko (it's not Goko's fault, don't worry)
Twitch allows cropping ("highlighting") videos, and can upload directly to YouTube.
Twitch doesn't save your past broadcasts by default, you'll want to enable this on your account.
Video editing softwareWindows Movie Maker (comes with Windows)
v2.6 for Vista/Win7 video tutorialCamTasia Studio Costs money to use, but there's a 30-day free trial. CamTasia is more powerful if Windows Movie Maker isn't doing what you want (like split-screen videos, most notably)
Comes with its own video capture software as well, which is quite nice.
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EDIT 2: The only thing I think this outline is lacking is some kind of tutorial for Mac users. I'm going to be completely useless here so if anyone else has good resources to add to this, let me know here and I'll update this outline and all of the places it ends up.