http://www.whitefordresearch.com/produc ... e-preorder
I also wrote up my notes on the SD card interface here:
http://41j.com/blog/2016/08/the-esp8266-and-sd-cards/
I've also been able to get the SD card working with the native esp-open-sdk using MetalPhreak's SPI library with some modifications (critically to enable duplex transfers).