Image courtesy of SparkFun Electronics

You can use this full-size breadboard in all your projects to add additional circuitry to your Arduino. It will give you twice as much prototyping space as a half-size breadboard. The breadboard has two power rails on each side for both power and ground connections. The break in the middle makes it easy to mount integrated circuits to the breadboard.

Buy a full-size breadboard from Amazon, SparkFun, Adafruit, or Newark.