In the meantime, my local Wal-Mart doesn't exactly have an impressive organic section. When possible, keep an eye out for organically grown produce from the following list, which was part of the report from the Environmental Working Group that identified foods in the conventional, non-organic food supply that contained the highest number of pesticide residues.
Since I can't find any of these organic, I soak and wash well using equal parts vinegar and water, and wee bit of soap.