In general I charge the following in US dollars:
Pencil Drawing - $25 for one character, add $10 for each additional character.
Inked Drawing - $60 for one character, add $30 for each additional character.
Colored Drawing - $100 for one character, add $40 for each additional character.
Drawings may include a simple background. If you are interested in more detailed backgrounds or sequential art scenes, we can discuss it. In general though, people don't usually come to me looking for masterful renderings of architecture. 8)
As for content, I prefer to avoid extreme violence and scenes involving politics or religion. Basically, let me know what you had in mind, and I will let you know if it is something I would do a good job of. Also, I don't like drawing other people's characters without their permissions, so I don't do fan art.
Please contact me if you are interested or have any questions.