Ask HN: How to approach enterprise prospects [COLD]

anyone have any advice on approaching enterprise-level prospects relatively cold? - I'm in SF/LA for the next month and have an opportunity to do live demos with big agencies here, however, I have no "ins" to these firms. Especially the executive producers/account managers who aren't necessarily the most active in networking and tech but who ultimately are the decision makers.

In short, my startup (firstcutpro.com) built a collaborative video review tool for video professionals. Think pivotal tracker for video production.