While it's very important to wash your produce since you don't know how many hands have touched your tomatoes or manhandled your melons, there's no need for a special cleaner. Soaps or washes can leave a residue, and they aren't any better than plain water, so save your money.
Even if your produce is organic, it still needs to be washed since bacteria such as listeria, salmonella, and E. coli can lurk on all fruits and veggies. Wait to wash your fruits and veggies until right before you're about to eat or prepare them. Wash all produce, even the ones that are pre-packaged and say "pre-washed." Wash all parts including rinds and peels you won't eat and stems you throw away since bacteria can be transferred from those parts to the parts you eat. Wash all fruits and veggies under running water and gentle scrub each one with your fingers for 60 seconds. It may take extra time, but it's better than getting sick.