There used to be a really good guy on youtube by the name of ChosonNinja or something like that. He was GREAT. I think the haters and just all the negativity he got finally caught up to him though.
Yeah, I remember him, had alot of very good vids. Sad really, he was actually a very modest guy, and I seem to remember him apologizing for annoying people before he vanished...

Also, no, you cant learn a art on your own. Some techniques maybe, but thats it...if you actually get the form right that is. Can promie you one thing; if you try to learn a technique at home and its added to mucle memory wrong...its going to be hard to learn it properly if you start at a proper school.
As for tai chi...if you speed it up, it turns into something different

Here its what many art calls drill sparring(some do freefights aswell).