Okay, I have decided to buy the Peavey Valveking 112 with all of those threads about it (lol) and I read that you need to change the speaker and tubes and can somebody recommend a good speaker that can play all sorts of things and some tubes that can play all sorts of things? Could also someone link a video or a guide on how to change these things too? Thanks.
For the tubes and speaker go here


or here


As for videos about installing tubes and speakers I can't help you out with those. There's lots of useful information at both those sites (they're roughly the same thing).
What style of music do you plan on using it for?? This will make a difference as to which speaker you will want.