Is there an auto focus adapter for Nikon lenses to Sony DSLR's?

I'm a Nikon D5100 owner with a 18-135mm f/3.5-5.6G ED-IF AF-S DX and 70-300mm f/4.5-5.6G ED IF AF-S VR lenses and I'm highly considering upgrading from Nikon to Sony. I'm interested in the Sony A77 DSLR. Is there at all an adapter (price range doesn't matter) that will have auto focus working with Nikon lenses converted to Sony cameras? The only ones I can find are manual focus. I kinda doubt there's anything out there that would help me but I thought I'd give it a shot. I'm guessing I'm just gonna have to start all over with the lenses. It would just be nice and handy if I could somehow convert my Nikon lenses to the new Sony, in the best way possible.

Through the end of January, Sony is running a sale for $200 off the kit with the 18-135, which makes the price difference between that and body-only about $100. If such an adapter exists, it probably costs about that much anyway. If you plan selling your D5100, you can add $100 to the price over the body-only anyway.

No - autofocus is dependent on the camera-to-lens communication and is proprietary for each brand camera. And there's not really a one-to-one conversion as each system has it's own method of focusing the lenses.

Besides, adapters don't work very well.

There are some 3rd party adapters, but they typically change the focus so that you no longer have infinity focus, and the quality of the result is questionable. And the lens must be manual focused as well as manual exposure must be used, which will be fairly difficult with G lenses.

If you want to preserve your investment in your Nikon lenses, you should stay with a Nikon DSLR.

Have you considered an upgrade to a D7000 or D600?

Sorry, such a thing does not exist. But the news gets worse. There are things that Sony dSLTs can do, that no Canon or Nikon cameras can do, not at any price. So if you have your heart set on the A77, you will need to jump ship completely, and sell your Nikon glass and re buy a-mount Sigma, Tamron, Zeiss, Sony or Minolta glass for your new Sony camera.

Sorry bro. No such adapters. I know. But good news is that you will be very happy with a Sony a77! I'm a Nikon shooter and am very impressed with the Sony cameras I've tried. Namely the Sony a57.
I have a Nikon D7000.