MLG uploads VoDs for WCS AM to youtube and Liquipedia has links, WCS EU is on twitch IIRC and WCS KR is still behind paywall, those are like the only tournaments worth watching. Dreamhack VoDs are also only on twitch. Shoutcraft should be on youtube, simply because it's TB's tournament. Proleague VoDs are on youtube.com/esportstv in korean, but I have no idea why anyone would pay to listen to the English casters.
That's about it, unless it's one of my favorite players, I just watch whatever is live.