CDW, a Fortune 500 technology products retailer serving more than 250,000 business, government and education customers, filed on Friday with the SEC to raise up to $500 million in an initial public offering. The Vernon Hills, IL-based company, which was founded in 1984 and booked $10.1 billion in sales for the 12 months ended December 31, 2012, plans to list under the symbol CDW. CDW was taken private in a 2007 $7.3 billion LBO by Madison Dearborn Partners and Providence Equity Partners. J.P. Morgan, Barclays and Goldman Sachs are the joint bookrunners on the deal. No pricing terms or exchange were disclosed.