There are two basic schools of thought when it comes to vendor management: Squeeze them as hard as you can to get the lowest possible prices, or turn on the warm-and-cuddly to build a more collaborative relationship that can bring better service.
It's especially difficult to know which way to go if you are the CIO of a midmarket company, since such businesses typically don't receive the sometimes slavish attention that vendors afford to their big corporate accounts.
The tips offered in a recent CIO.com article tend more toward the cutthroat than the cuddly. Some examples: Search the Web for price information to use in negotiations. Lure away a sales rep from the vendor so you can leverage her knowledge about the company's inner workings. Play up an interest in Google Apps.