A couple things: sales leadership and company culture are very closely linked. The sales management style at an AT&T kiosk is much different than the sales management style at an enterprise software startup. Try to find someone not necessarily in the same space, but in a company that closely aligns with your company's culture.
Next, find someone with a proven track record of leadership. There's a big difference between a manager and a leader. You don't need to hire them, just take them out for coffee (or, hell, find them on Clarity :)). But they have to be a good leader. See if you can talk to their direct reports, or surreptitiously ask your friends/network if they have a manager they look up to.
Ultimately, management is about people, so the industry really doesn't matter. A good sales leader can inspire the team without having to know the ins and outs of the industry or product.
