I'd be grateful if someone could answer the following: to what extent would Pete Thomas' Sax Instruction DVD be pertinent for 1) the tenor and 2) the soprano? It is made for the alto I know. If not suitable, is there anything else for a beginner on DVD?
The DVD is general - no need to worry which instrument it is.
Instrument differences come in when you start playing music with other people or a CD, then you need music that's right for your instrument pitch, but until then you can pretty much play anything. Only thing to watch is that music scored for other instruments may be scored outside the range of a sax. Clarinet is a good example.