An easy way to convert photos to paintings is to use Topaz Impression plugin.
The program contains over 100 different presets, ranging from simple charcoal sketches to oil, watercolor, and even impasto styles.
You can control brush width, length and many other parameters, and in addition if you "paint" on another layer(s), you can selectively remove or fade out some of the painting effects to reveal more of the original. In other words, you'll get a lot of flexibility to add your personal touch to your paintings.
For some examples of the painterly renditions by this program, you can view my Digital Painting gallery at Fine ArtAmerica.Painterly Images
Here is the link to the Topaz Labs plugin: TOPAZ IMPRESSION
Using "lespalenik" discount coupon, you'll get the Topaz Impression plugin for $15 off (regular price $99.99)