I've worked as a freelance illustrator since 1989 for a range of companies including Harper Collins and Mentorn. I have worked on Children's books, advertising, comics and design for television. To commission work contact firstname.lastname@example.org.
As a ball park figure, I charge @£50/hour for illustration and design work.
I tend to be very generous regarding what counts as a chargeable hour, and apply discounts for interesting work, and good causes.
Before commissioning something, it's worth thinking about exactly what you want, and what it will be used for...
Do you want original artwork to hang on a wall? If so, what medium would work best... watercolour inks? Acrylic paint, or a print of a digital image on archive quality paper?
Do you need a design sketch to help pitch a TV show? If so does it need to be small enough to email? or large enough for a poster?
Do you need finished artwork for print publication? If so will it be full colour or spot colour, black and white or greyscale?
All these areas have different requirements, and I'm happy to discuss what would work best.