We have been trying to find a solid permission-based email marketing/contact management system for our clients that is affordable and actually works. We have found it with a small business in Phoenix that created a product called Promoterz.
For $150 month you can have a complete suite of services that allows you to capture emails of customers and stay in touch with them while also see what they are saying about you. It’s a great product and it works. Oh yeah, and the company is made up of some very cool, competent, trustworthy guys.