The try-it-before-you-buy-it concept has expanded with Nokia's plans to open at least 25 “experience centers” in more than a dozen North Americanby fall. The 200-square-foot stores let buyers try phones with all the latest wireless gizmos. The shops don't sell phones. Tech experts provide shoppers with easy-to-understand information, then refer them to nearby retailers. Similarly, the Westfield Group is working with Intel Corp. on a series of experience zones spotlighting Intel partners Gateway, Microsoft and Sony at mall kiosks.