why not try out one of the services like aweber. You can import your mailng list and do a trial mailing to see how it works. maybe segment your mailinglist before so you don't get into trouble re spam etc.
Yes, once you get your list into one of these services it will really be worth it to you. Constant Contact would probably ask you to request another opt-in when you import your list which basically means asking everyone if they still want to be on the list. You might end up losing a large chunk of your subscribers when you do this but I have found it is better in the long run to start with a clean list of real subscribers so you can get a better idea of how your email campaigns are working.
I have a member base of clients who have all registered to be on my newsletter. I sent 6500 out in August and got 3 spam hits, Constant Contact have now refused to deal with me? This is after an 18 months relationship. I really found it strange. I called them and allthough the lady was very nice they have a real unusual spam policy. I wouldn't use them again.
That's strange. We get one or two spam hits every mailing we send out with no problems from CC. Were there any other circumstances they mentioned other than the spam hits? I'd hate to have our account closed.