Hmmm,
Definately Tamiya imo.
Their StuG III Ausf B is a great kit for a newcomer - the Hetzer too (I'd look at the 1/35 scale ones to start with).
If you want a proper turret the Cromwell is nice as is the Panzer II French Campaign which I'm currently working on.
These are all affordable and not mega expensive like their newest stuff.
There's always the Dragon Cyber-Hobby range too. A T-34 would be a good choice as would a basic Sherman.
I haven't read the whole thread - have you mentioned if you want Allied/Soviet or Axis or modern armour.
The early Tamiya is a good place to start looking? Cheap and simple but very effective. I picked up their Marder II for £15 and that built up beautifully.
Let us know what you get!
Ben