Corporate Headquarter Contact

How can I contact Dell's corporate directly? I've been a loyal customer for more than a decade. Recently my Inspiron laptop has stopped working after about a year. I talked to Dell tech support, and they informed me that my laptop is no longer under warranty. I just missed it barely by two months. They said they can't do anything for me, and that I would have to pay about $400 to get it fixed. For 12 years I've only bought and owned Dell computers. I just missed warranty by 2 months and they couldn't do anything for me. I've been a loyal customer until today. I can use the $400 to buy a new computer, but certainly will not go towards any dell products.