To power the IR leds.  A power supply tends to be more suitable for large numbers of LEDs as volt adapters often have a low current rating. There are several options that are easily available.

PC Power Supply
These power supply are what are used in a desktop computer. Since most people will have one running in there setup this is one of the best options. On the power supply are adapters that are used to connect to a drive with 4 different color wires.

Red=5v
Black=Ground
Black=Ground
Yellow=11v

There are splicers available allowing you to have more of the end connectors. If for any reason you don’t have a computer in your setup that uses this type of power supply you can still use this as an option. On the biggest connector coming from the powersupply (Used to connect the mother board) is a green wire surrounded by two black wires. Shorting the green wire to one of the black will start the power supply.

USB Power
If you are using a laptop one option is to use the power that is in a USB port. The port caries 5v power. The cable are as follow:

Black=Ground
Red=5v
Random Color1=Data
Random Color2=Data

This power can be accessed by just cutting the end off of one of the many cable you may have around the house.

Wall Adapter/Transformer
This is a device (as pictured above) that transforms AC wall power to a DC power and is normally found with small electronic devices. The voltage that the transformer provides is normally stated on the label as “output power”.