Some answers, at least in my opinions...
1) This is totally a style issue. I've played in pbp games where DMs roll their own dice manually and just tell players the results. I've been in a game where the GM did what BH suggested - she rolled on Invisible Castle, posted just the result in our game, and if anybody had a question she could link it. Finally, I've played in games played through AIM where the DM rolled all the dice just like the players.
It's entirely a style issue and should go by what you're comfortable with. As was said, making all dice rolls in the open can lead to metagaming in some instances, so there are drawbacks all around.
2) I believe this works, too:
GobO_Fire rolled 1d100 and got a total of
14:
It just won't show a pretty picture.
3) Again, this is a style thing. usually (not always) if a GM makes a book available, it's optional for the player to use, so if they don't use it they don't need it. Often (but not always) the GM should have a copy of whatever material the player is using.
4) I started on WotC shortly after 3e came out.