Unless you are used to using a meterless camera, I would strongly suggest a M6. Don't purchase a M2, M3, etc. just to save money - buy one because you love the way of working they embody and excel at.
As much as I like Voigtlander (I own four of their lenses), I'd recommend a Leica lens for your first acquisition, specifically a Summicron 50mm DR or rigid. If you look around, they're not much more expensive than a new Voigtlander Nokton 50, 40 or 35. A Summicron 50/2 will give you the classic Leica look from the late 50s onwards: excellent, distinctive bokeh when wide open, razor sharp when stopped down, and the signature Leica "glow" or "bloom" in the highlights. Not only is the Summicron 50/2 an excellent introduction to world of Leica optics, it's a lens you will likely keep and cherish for a very long time (instead of wanting to sell it or "trade up" in six months).