I would think all speeches will be on youtube very quickly but you can see the speeches using ustream.tv, it is what the GOP is using for the convention and is pretty good. You can see the speeches live or watch the replays right there.
I am so looking forward to Rudy tonight, a perfect warm-up for Sarah, I hear Rudy is stepping it up more than usual and is very fired about about everything going on so look for a great speech to warm up the crowds