Uno SMD R2 Fried ATmega

In a moment of clumsiness, I accidentally put 12V across an input on my SMD edition Uno. As soon as power was connected, my PC crashed so i whipped out the USB and turned off the power. Now avrdude say: stk500_recv(): programmer is not responding. Whenever I attempt to program the board the RX LED will flash, suggesting that there is still life in the the circuit. I accept that the ATmega is kaputt, but I was wondering if anyone has had any luck replacing these? I'd rather not fork out for a new Arduino, but I don't think I can last too long without one.
Thanks,
Jon

(deleted)

"I don't think I can last too long without one"
So why not make one up your own? Only need a few parts:
ATMega328P-PU
16 MHz Xtal, two 22 pf caps
four 100nF caps: Vcc, Avcc, Aref, DTR
10K pullup resistor for reset
optional if want a 5V regulator: two 1uF caps, 7805 regulator
connectors as you desire: IO pins, FTDI header, ICSP header, power
piece of perfboard to mount it on
All can be had for little money from www.dipmicro.com
If you want the ATMega to come with a bootloader, you need to get it elsewhere.
Reply #182 on "page" 13 of this thread shows ex example of just that, with a '1284 processor.
http://arduino.cc/forum/index.php/topic,80483.180.html
Arduino Forum

Thanks for the help, I think I'll build my own on breadboard and tackle desoldering the SMD at a later date, once I can program the boot loader onto a replacement.

To fix your uno quickly and easily:
Buy a UsbTiny programmer to bootload your arduino. They are only $15 at Sparkfun (the AVR Pocket Programmer, Sparkfun's version of the USBTiny). They are a great deal. When you bootload the arduino it should make the RX and TX LEDs blink appropriately when you upload. When I have the RX led or the TX led blinking when I try to upload, I use my AVR Pocket Programmer. I think that this should work. If it doesn't work, you will have a great bootloader (that you will probably use frequently like I do). Do not worry that your Uno will not show up on the com port, because this programmer will fix it.

Note: When you are using this programmer in the Arduino IDE, you will have to select USBTiny for your programmer and Arduino Uno for your board. Do not select a com port for there will be none to choose for your programmer. Then plug in the header of the programmer to the Uno's ICSP (on the right hand side) and press burn bootloader in the tools menu. After about a minute, the IDE will hopefully say "done burning bootloader" with no error messages.