@thecoolest. Thanks for information about SD.
Hi @daniel. You tried the library on Nano or other Arduino boards?
For me the code you posted is strange. I already see it before but in the comment part there are some information for me very strange.
SCL and SDA are the names of pin for I2C wiring and not for SPI. The pin for SPI are MOSI/MISO/SCK and SS o CS
Pins SCL,SDA,MISO,MOSI and SCK are fixed in every Arduino (not the same on Uno or Mega).
Other pins can be assigned every you want. But not this special pins.
Are you sure to know the Nano pinout? Can you see this very good pdf:
http://www.pighixxx.com/downloads/arduino-nano/
http://forum.arduino.cc/index.php?topic=151646.0