Before you pick up the phone to call a vendor, walk down the hall and understand what your internal options are for free list growth. For example:

• Consumer touch points: Most brick-and-mortar, catalog and call center operations now ask for your email address as a natural course of business. In fact, it’s written into their script. Determine all of your company’s consumer touch points and make sure your interests are being served.
• Offline campaigns: Much has been written about how traditional advertising can drive prospects to a website. However, don’t assume that the first thing they’ll do is sign up for your newsletter when they get there. More than likely they will be preoccupied with the call to action that got them there. Add a simple line of text, such as "Be sure to sign up for our free newsletter" to all direct mail and print creative. You can even include the url string, but only if it’s simple and obvious such as "www.xyz.com/newsletter."
• Direct mail lists: Speaking of direct mail, it is commonplace for companies to conduct friendly direct mail file exchanges from time to time. These are usually free, one-time uses that have plenty of caveats. I have long been an advocate of well-executed email swaps but, as you can imagine, with about triple the caveats. Don’t simply swap files and send or you’ll end up with a result that’s the polar opposite of the one you’re seeking. Craft a co-branded introductory email that explains why they are receiving the offer and why it’s valuable to them.