I used worth100.com
Basically it`s an graphic design contest where up and coming designers create a design based on what you want. The contest runs for two weeks or so and as many designers can submit a designs. Once closed you pick the winner and they get the credit. In total it cost me $100.
The logo can be found on my site www.consumertreehouse.com
It`s perfect for my site, not too serious, but serious enough.
Good Luck
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The ConsumerTreehouse.com Team
www.consumertreehouse.com