If you don't need to watch it live, you can torrent the race in HD. I usually get my links from Reddit, but Rathburn uses a torrent site which has reliably been faster at posting races.
Yeah, you can find some pretty good HD torrents. smcgill is the guy who uploads the best ones for F1, just google that guy up and get his itshay.
I'm way too way too lazy for that these days, so I just PVR it off of TSN HD and watch it that way. At least you can fast forward the commercials, and other than watching live, it's the quickest way to get it so I can watch at my leisure. Sometimes the torrents take forever to get uploaded.
Once the F1 streaming dealio becomes a real thing, I'll look into it.