An obvious but important tip when it comes to bulk email marketing campaigns is to ensure all the email addresses are accurate. Don't waste your time going through your list of contacts to correct typos or calling your customers on the phone to get their email address. This is a huge waste of time.
Never email a customer without getting their permission first! When you email your customers without asking them, they may think you're a spammer and not read them. This can cause backlash against your profitability in the form of customers opting out of your email lists, and can even result in problems with your web-hosts and internet service providers.
As with food, the best email lists are those that are cultivated organically. Don't purchase a list online. Use business cards to build your email lists, and use sign up forms for followers. This will guarantee your list remains relevant and it will promote business growth.