Hello (: I this tutorial I will show you how to put a brush on you Adobe Photoshop from an image pack.
I will be using this image pack from Outspoken-Kate.com (: (You may use the same, Credit to Outspoken-Kate.com)
STEP 1: Open your image pack from your computer!(I have resized mine so don't use this one I have above!!)
STEP 2: Use your Polygon lasso tool

To make a box around the brush you want like this:
STEP 3: After selecting the box go to edit>define brush
And you continue to do that to all the images and that is it!!