That's okay. Now that you are implementing a review process, start collecting them. Reputation Builder works great on mobile devices (iPhone, Android, iPads, etc), so you can just add the customer's name and email address while they are at your place of business.
The Reputation builder offers a "kiosk mode" feature, that great for using while your customers are onsite. There is also a Unique Feedback URL that can be added to printed media, invoices, bills, tabs, receipts, business cards, QR codes, SMS, etc - and does not require you to know the customers email or name.