i wrote a library for control a 7-segment display(common cathode) with a 74HC595 ic.
Download -> Library
LINK -> Description, Pin connections
//Object initialisation
AH_74HC595(int SER_Pin, int RCLK_Pin, int SRCLK_Pin);
//Register functions
void setPin(int index, boolean value);
void setAll(boolean value);
void setValue(byte value);
void shift(boolean value);
void rotate();
// 7-Segment display functions
void showNumber(byte number);
void showSign(char sign);
void setPoint(boolean value);