I recently looked online for something better, and there are sand rakes they use to clean up beaches that look perfect. There's one called the Shake-N-Rake that looks promising, easy to make at home. There are also some that you just drag thru the sand to collect the stuff. Happy hunting!
It may sound strange but a carpet grooming rake works really well on sand. I got mine from amazon. Alot of small tines that comb the poop out leaving clean sand behind.