Ill be getting Total Warfare and the tech manual (and TRO 3025 if I can find it) soon but i need some advice on what else to get.
Aside from regular games with 2-4 players duking it out, I was planning on doing a campaign with my players where ill be acting GM and controlling the NPC opposition, and the players will act out their own pilot and possibly a few supporting troops.
Something along the lines of old RPG type boardgames (hero quest) and such as Necromunda/mordheim.
Is there a good supplement for BT that gives rules, scenarios and advice on sessions like these and which ones?
Ah! I remember Hero Quest! Nice!
Using that as a frame of reference, I think the Starterbooks would be up your ally. Starterbook Sword and Dragon is a great place to get your feet wet. The Starterbooks have Player Force rosters and personnel already drawn up, so it's easier to get started.
Beyond that, Total Chaos has a much bigger "sandbox" and very open ended. The pro is that the players can design their own unit from scratch and there are a lot more possibilities and all the advanced Jihad era tech is available. For a beginner however, the con is that since it is so open-ended, it's easy to get a bit lost and or confused.