Hi, David, I'm a professional illustrator. The best course to follow for getting serious illustration clients is to be listed in the directories of illustration that are used by all ad agencies, publishers, media, etc. who buy illustration.

The ones I've used are Directory of Illustration in the US.
They publish a large print book annually that you buy a page or pages in showing your work, and also have online sites that illo buyers can access.

Don't waste your time on "shows". The art directors who buy illustration use the professional directories.

Here is the D of I site.


http://www.directoryofillustration.com/

By the way, more illustration is now being purchased because the reproduction rights for photography have increased so much (mostly due to higher model fees) that illustration is a bargain in comparison.

Make sure she has good contracts to protect her rights and understands the reproduction rights and fees for use that are fair.

An invaluable tool is the Handbook of Pricing and Ethical Guidelines published by the Graphic Artists Guild.
www.gag.org

Alice
btw, here is my web site

http://www.aliceflynn.com