WD Makes Good
Now that Dell has been refunding $50 to a lot of people who didn't get an ATA card (including me), WD has decided to step in, and send controller cards to those who are "eligible."
From "Dell-Chandler":
For those customers who did not receive a controller card but did order the Retail Kit SKU (A0080840) process is:
Customers will need to call Western Digital Customer Support Department at 800-275-4932. They will need to have the drive serial number handy (located on the drive itself). They'll just need to explain that they ordered the drive as part of the Dell promotion, give their name and the drive serial number (which will be checked against a list) and a Controller card will be shipped to them if they are eligible.