I want some cartoon illustrations for a book that I've written

I have written a guide on weight loss and healthy eating. The theme of the book is based around delivering effective advice in a simple, easy to read manner. The cartoon illustrations that I require will be a big part of making the book simple to understand and enjoyable to read.

Depending on the cost, there will be approximately 41 little cartoon illustrations in the book. If you could design the cover as well, I would be interested. One of your sample illustrations (the man by the flip-chart) is the type of style I am thinking of, although I am open to other ideas. Could you indicate what you think the overall cost would be?