Book Cover Design/Illustration For Percy Jackson type middle grade book

Book cover (front back and spine) needed for Percy Jackson type series. Looking for design similar to those book covers
Please check out the following links for examples:
http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Ddigital-text&field-keywords=Percy+jackson&x=0&y=0

http://www.amazon.com/Christopher-Pepper-Chronicles-Silver-ebook/dp/B005AHP0KS/ref=sr_1_1?s=digital-text&ie=UTF8&qid=1326307878&sr=1-1

http://www.amazon.com/Battle-Blue-Glacier-Adventures-ebook/dp/B006IW100I/ref=pd_sim_kinc_6?ie=UTF8&m=AG56TWVU5XWC2

Please respond with the following:
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