I will offer you a word of caution.
Most packages FARM for email addresses, and most people that are selling email lists are FARMING email addresses.
If you do not have a solid opt-in program you are going to get slammed for spamming.
Just a heads up, maybe you already have this covered, if so, please disregard and good luck with your search.
Regards,
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Midnight
Excellence is not an act, but a habit - Aristotle