https://github.com/skorokithakis/tiny-ESP8266-breakout
If you want to just order one, here's a paneled PCB of the earlier versions (the only difference is pretty much the lack of a 3v3 out, plus the traces aren't as pretty): http://dirtypcbs.com/view.php?share=15302&accesskey=
Technical details: There exist some breakouts like this one[1], but they're crap, stay away from them. They don't include all the necessary pullups/pulldowns for the ESP to start running code, they don't include a capacitor and they don't leave room on the breadboard for connectors, so they're useless. My PCB fixes all these problems by adding 0805 10k Ω resistors, a capacitor and by being less than 2.5cm in each dimension.
[1]: http://www.ebay.com/itm/ESP8266-ESP-12-WIFI-UART-Serial-Modu...