Being able to draw and read a load line is the key to all of this tube stuff. If you can take a date sheet and plot one. You can design an amplifer.It's not hard and dosen't require a lot of math. If I can do it anyone can (Everytime I start a project I have to hit the books and refresh my memory)
There is an excellent article at http://boozhoundlabs.com/howto/
He walks through the whole design of a 6v6 amp. The first few pages are a great into to load lines and op points. Read it a cople of times till you can draw your own, say at 200V or for a 3k load.
There will be a quiz tomorrow, so everyone bring a #2 pencil to class...John