We want to offer a reseller program with a discount if they purchase 6 items or more. I know how to add the discount if it is for the same product - but we want to offer if they purchase 6 of any product on the site get all 6 at a discounted cost. (same discount for each product) Is there a way to do this?
For your requirements you need to use Magento Catalog Price Rule and Shopping Cart Price Rule from admin. Using this, you can give discount to the customer according to your requirements.
Let me know if I understood you incorrectly.