Photoshop: Brushes
There are a plethora of brushes available to you on photoshop. This guide will explain different brush settings, as well as how to install different brush packs here on deviantART. This guide is for pressure sensitive pen tablets. It is going to be much easier to do things with a tablet. Ones by Wacom are good, and you can get a bamboo for under 99$ USD.
Basic Brushes in Photoshop
It's important to stick with default ones to learn all the settings. You can do so many things with the hard round brush.
Bring up your brush palette in one of the following ways. (note I am in CS3, so the icons will look much older, but same