I am surprised when I find a local business or organization—restaurant, retailer, non-profit—that isn't using an email newsletter service to reach their loyal customers and clients. Email newsletters offer a wonderful opportunity to follow up with clients, reminding them of sales, trunk shows, happy hours, bands, giving opportunities and more.

Building this sort of "club" mentality is an important part of your sales funnel, resulting in longer-term customers who feel a bond with your brand. Advertising, marketing, signage and sales fill the top of the funnel—bringing in people who know only a little about your business and who hopefully have a good experience that first time.

The next step, though, is to filter down to those folks who want to get to know you better and engage with them so that you can get them to come back. Part of that strategy should be good email newsletters.

First, you've got to get the addresses. For retail, I suggest an opt-in at the cash register; for restaurants, put a simple reply card (name and email) in their check holder. If you've got a low-fi setup for transactions, you can simply ask your customer to fill out a card with their email address on it or to drop a card in a fish bowl. Tell them you're signing them up for your newsletter and give them a rough idea of the frequency. ("We send out a newsletter every week with our lunch specials," or "We send out the newsletter whenever we get a new shipment of shoes, plus to tell you about our monthly sales.")

If your cash register is a little higher-tech, you might ask if your customer wants their receipt emailed to them, and, if they say "yes," if they'd also like to sign up for the newsletter.

Other options include a giveaway or coupon in exchange for the email address, or you could post QR codes on signage in the store so that smartphone owners can sign up for the newsletter on a whim. Of course, you'll want to put a sign-up form (which your software will help you create) on your website and on your social media landing pages, as well as any directory listings that you've claimed (Google, Bing, Local.com, YP, Yelp, etc.)

Once you've got some email addresses, what are you going to do with them? Here's what you shouldn't do: If it's more than a few dozen addresses, don't send them as "CCs" or "BCCs" straight from the store's email account. You could find yourself in a bind, where other people's email services blacklist your account for sending "spam." You could also get in trouble with your own ISP for sending too much email at once.

Instead, sign up for an email marketing service; not only do they handle the behind-the-scenes work, but you'll get templates, support, advice and in many cases, additional features that you can add when you need them.

At the JFP we use two different services. Constant Contact, which we are using for JFP Daily (constantcontact.com), is certainly making a play to be the mindshare leader. In fact, they've just published their own book, called Engagement Marketing (engagementmarketing.com) that offers advice on exactly what I'm talking about—moving people from new customers to engaged members of your "club."

Constant Contact offers full-fledged email service, including the ability to build multiple lists of email addresses, creative emails and newsletters with attractive templates, and tracking and reporting features so you can see what works and what doesn't. They also offer event marketing and management (it's what we use for RSVPs to the Best of Jackson party) so that you can send out invitations and reminders, and generate a list of RSVPs at the door.

The other service I use is MailChimp (mailchimp.com), which is noteworthy because of how well it integrates with a number of other web applications such as Drupal, WordPress, all sorts of CRM, or Customer Relationship Management software, GoToMeeting, FreshBooks accounting, and many more. That means we can enter customers once in software that's used to capture them as leads and then moved over to MailChimp to actually fulfill that lead.

Another feature I like in MailChimp is the Mail Beamer, which enables you to send emails to MailChimp that are then broadcasted to your list. That's handy when you don't want to go through the whole process of putting together a newsletter via template, but you want to get something out to your list quickly. MailChimp also offers RSS to Email that can send out email alerts whenever you add blog entries on your website.

MailChimp offers some fun mobile services, like an off-line sign-up feature for the iPad, enabling you to gather email addresses while you're working show booths or outdoor festivals and fold those folks into your marketing system.

These are only two of the many email services available. Find one in your price range with features that appeal to you; that's half the battle. The other half is to offer more than sales and sales pitches—you need to offer value in your newsletter as well, such as tips on flower arranging or fashion styling or wine pairings or legal need-to-knows. Offer a little insider information in your "club newsletter" and you're on your way to creating a fanbase that helps you build and sustain your business.