Bulk Emailing

I need to send 2-3 thousand email a day to C.L. Ad posters. Must be able to send each mail with its assigned subject,(Provided) Must send at a slow pace or varying pace to stay under the radar. Must have the ability to rotate the from email address, and or switch smtp accounts. (If that's not necessary, you let me know) Must be able to track opens. If you have this software already, you can install it on my server, or suggest the best solution. OR- If you already has this service working, and you would rent the service to me for a fee. Which ever works out best for both of us. Anyway.. waiting for the right person who can implement this task or make the best solution.