Soon the Zeiss 50mm f/1.4 SSM lens will hit the market (in late Spring) but for many of us this lens will be too expensive (rumored price is $1600-$1700). If you can wait 12 months more than you might can get a cheaper and still high quality alternative from Samyang! Fotogears (official Samyang Asia partner) worte on their facebook page that a new Samyang 50mm f/1.2 A-mount lens is on the Samyang roadmap and could come in 2014.
I like Rokinon/Samyang lenses a lot and I recommend you the following two lenses for Alpha mount:
1) The 35mm f/1.4: In US you can find it as Rokinon at Amazon (Click here), Adorama (Click here), BHphoto (Click here) and on eBay (Click here). In Europe the name is Samyang and you can find it on eBay (Click here) and with the name Wallimex again on eBay (Click here).
2) The 85mm f/1.4: You can get for $274 on Amazon (Click here), branded with the name Rokinon on eBay (Click here) and branded with the name Samyang on eBay (Click here).
And here are the links to the newly announced Samyang/Rokinon lenses:
8mm f/3.5 fisheye at Amazon, BHphoto,
14mm f/2.8 at Amazon, BHphoto,
24mm f/1.4 at Amazon, BHphoto,
35mm f/1.4 at Amazon, BHphoto,
85mm f/1.4 at Amazon, BHphoto,