> checklists ... where do they really fit as far as how we file them
Make a list of ones for each desired time scope - daily, weekly, monthly, quarterly, ... Store them wherever makes sense; in Outlook, Notes are a good place to put them.
> handling reoccurring tasks
I'd put the task in the calendar as a recurring appointment, set to repeat accordingly.
> applying the system to a busy sales career
I'm not in the field, but here are some ideas and resources:
o keep a checklist of all clients, which you review weekly and ask: Do I need to do anything to deepen the relationship?
o make each client a project, but rename the project based on the client state, as the sale goes through: qualifying, etc.
Hope that helps.