Cover Ideas Needed

Dear Friends:
One of you gave me the idea for the cover of my second book, now I need ideas for the cover of the third book, JUSTICE FOR JOSHUA. Without giving the story away, the following location descriptions might pique your imagination?? PLEA FOR COVER HELP JUSTICE FOR JOSHUA (A brief, brief synopsis) I'm shopping for a cover for my new book, "JUSTICE FOR JOSHUA." Most of action takes place in Oakland at train station, Oakland Port area where the giant cranes are, Emeryville in an auto wrecking yard, an independent Oakland Cab co. (Veteran's Cab), a 3 story Victorian home in Alameda, (where a gang hangs out) and places in between. Josh uses his strengths as a world champion Oriental Martial Arts champion to try to avenge his wife being shot in a drive by shooting. As usual, a box of See's candy to the winner. My eye doctor won for the cover for JOSHUA'S REVENGE."
Thanks in advance for any ideas.
Richard