If you've got over a thousand subscribers, why not look at monetizing them via Aweber. Disclaimer: Aweber doesn't pay me, I just think they rock. It's not expensive, and it is easy to take your regular blog newsletter and insert paid ads, etc. It's not free, but if you've got a thousand subscribers it should more than pay for itself. I know someone who has a seriously popular blog who says she makes more than twice as much from ads in the newsletter as in the blog. Your mileage may vary, obviously, but it's not pricy. I'd give it a go if I were serious about email newsletters.