that seems to be a lot of $ for a DVD. No doubt the producer/s spent a lot of hours on it.
I have always been of the opinion that a tube amp is not for the raw beginner. There are high voltages present, which can be fatal to some, and neatness in wiring, layout etc etc are all very important.
Also, good soldering is an ABSOLUTE must!, especially because of the high voltage and in some case high currents, ie filament supplies.
You did not state if you have built electronic kits before?
You would probably be better off to buy a good quality kit for a tube amp, such as the Dyanco ST70 clone from Tubes4HiFi, or some of the kits from Parks Audio as some examples, do a search, as they all come with excellent step by step instructions.
As I mentioned above, to build an amp say from a diagram that you found, you really need to have some basic understanding of electronics and tube circuitry and be fairly handy with the soldering iron.
