I use ixactcontact.com - I had market leader before this. I had about 300 leads that I had to move. Ixactcontact did it all for me. I provided them with the list - they added them in.
The monthly newsletter is simple to set up. The hardest part is making your header for the top of the email. You only do this once.
Each contact has an amazing amount of info you can add and then sort.
There is even a personal agent website - anther way leads can get to you. I have a link to my website for the contact page so that I can easily add a new lead in to the data base.