I've used TVAnts, Sopcast, Veetle, and pretty much all the others (StreamTorrent doesn't work good for me, but the rest do).
Under each event they have links listed under "P2P Streams" and "Webstreams". "Webstreams" will be the easiest to use, but you will need to install two things for many of them, both totally safe.
First, install Sopcast, as that's the one used the most (and the one that gets shut down the least). After installing it when you click on a link needing it the program will open automatically and start loading the channel, which can take a few minutes sometimes (so be patient), and it'll stutter at first, but once it gets going it runs great.
This is an automatic download link (as is the one below) so don't click on it if you're not ready to download it and wish to look into it further.
http://www.sopcast.references.tv/d2/SopCastOcx.zipAfter that install the IE plugin for Firefox.
https://addons.mozilla.org/en-US/firefox/downloads/latest/1419/platform:5/addon-1419-latest.xpiOnce they're installed when you right click on a link there will be a choice to "Open in an IE tab". Choose that for any link asking for IE, like Vexcast, NDSports (which is almost always good for me), Websop, etc.
let me know if I can help further. :)