You should probably use this thread now, but to answer your first question, it's just [motion] + [two attack buttons]. Jill and Shuma are in the XBL/PSN stores, but I think Akuma/Sentinel/Hsien-Ko/Taskmaster? are just regular unlockables that you get by playing versus matches/arcade mode. Or if you're talking about the newly announced characters like Iron Fist and Vergil and stuff, they're packaged in an all-new game that you'll have to buy when it comes out.