Dell is one of the largest distributors of personal computers in the country. Of all the distributors, they probably have the largest number of dissatisfied customers and the largest number of satisfied customers. Overall, their quality is pretty high as compared to comparably-priced computers, as is their customer service. I'd try their regular channels for customer service first -- you may get satisfaction sooner than trying to rattle cages from the outset.
However, if you want to contact the CEO, here's the address:
Kevin Rollins, CEO
Dell Inc.
One Dell Way
Round Rock, Texas 78682
United States