thank you guys but what i really need is the circuit that i can plugin the arduino !
This is why I hate Arduino...
Sorry to be rude, but electronics are not lego you can snap together.
If you want something you can plug into the Arduino and call it a day, then you should invest in the part you want. It may be pricey but it *should* immediately work.
If you can share some details about what you are driving and how fast you want it or how big the motor is, we can help design a circuit.
If we help you design a circuit, you will *need* to be willing to manually connect at least 8 components together for EACH H-Bridge. A stepper controller typically has two H-Bridges.
So... aside from the circuit you need, you have to program the Arduino to deal with it... the program will vary based on how you build your circuit. It could be a simple 2-pin solution (step and direction) or it could require 4 pins to directly control the transistors that make up the pair of H-Bridges.
Simple, no frills parts list.
4x PNP transistors.
4x NPN transistors.
Resistors (Assorted... to limit current into the transistor 'Base')