A good top-level article on how Marketers can build a strong relationship with Finance; check it out here.  Pretty simple really, but once again, you have to stretch a bit, and learn to speak the language (as you should be doing with IT).

If you’re struggling to find a reason to begin this relationship with Finance, I can provide you with a conversation starter.  I think you will find it opens the door to a wide ranging discussion with Financial people about how marketing should be measured and what the contribution of Marketing is to the Company.  The basic idea is to take the periodic accounting approach that Finance uses and twist it around to a customer accounting view.  Check it out!