Need pointers on working with a graphic artist

[Eric Lee]

I'm a text-and-database-oriented person who needs to hire an artist on a 
freelance basis to create a logo and other graphics for a web site.

Does anyone have pointers on how to describe for an artist what one is 
trying to achieve in such as way as to inspire imaginative handling while 
staying on the topic?

Pointers on related issues of working with an artist one has chosen are also 
welcome.

Thanks.

Eric Lee
ericlee at oise.utoronto.ca