This is my latest edited CardInfo.ino version uploaded to google drive as on 5th Nov '15 to display SD card size in GB too: edited 5Nov15 CardInfo.ino
The file size has increased from 12.53 to 14.29 kbytes since float variable had to be incorporated to perform decimal calculation.
Use SD Formatter tool to format SD cards to have it detected in Arduino properly - SD Formatter
In the 'OPTION' button select FORMAT TYPE 'QUICK' & FORMAT SIZE ADJUSTMENT 'ON'