Try the following module, this will resolve the problem
This allows customers to select “where did you hear about us?” option during checkout, this gets saved against order.
Here are the main features of this module-:
- Where did you hear about us dropdown comes during checkout?
- Dropdown list can be managed via admin under system -> configuration -> customers -> customer configuration
- Also comes with “others” option in dropdown which allows customers to add free text.
- This information stored against order which can be viewed against order in admin.
- Dropdown list also appears when you create phone orders from admin.