Email Marketing Automation

I'm looking for someone to help me set up a system that will do mail merges from excel to gmail. More intricate details are that each email should have a 5 minute delay and it needs to be able to automatically follow up on dates/times that can be customized. I also need the system to be able to send follow up emails up to 7 times. I have one computer that I just installed Linux on and have two more that currently are windows based. Need to know which systems will be best for the application. This will genuinely need to be a partnership because I haven't done anything like this before. The price is negotiable.