Hi wade74, you ask a great question and hopefully we can help. First off, what type of retail store are you running? Do you also have an online presence? Many stores offer feedback surveys on the bottom of their receipts, but usually offer an incentive such as a random cash drawing, percentage off your next purchase, or small free item (for example, a small restaurant might offer a free soda on the next visit). Once the customer completes the survey, they are provided with a code to redeem on their next visit.
If you offer an incentive, I think you should have a good showing of objective feedback depending upon how you phrase your questions. There are many vendors who already do this for a variety of large and small businesses, or you could set up your own questionnaire on your own website, or using existing survey sites, such as Survey Monkey.
We look forward to hearing more about your business, and survey objectives. We have many knowledgeable members who should be able to share their experiences with you as. well.