Don't do it! As far as I can tell, there's no such thing as a targeted list--unless you're talking about a strictly opt-in list. Otherwise, it's still spam, and your ISP can unplug you for it.
Your best bet is the search engines and directories. And if you have something different, you can e-mail press releases to editors. For addresses, try the EditPros Business News Media Directory at http://www.editpros.com/media.html. Most editors are receptive to e-mail press releases.