Audi’s A3 e-tron starts at $37,900 in the US, rolls out in October

If you live in the States and have been itchin' to get behind the wheel of Audi's new plug-in hybrid, you'll soon be in luck. The A3 e-tron "Sportback" (read: hatchback) will arrive at dealers in the US in October, with prices starting at $37,900 b…