It sounds like you're looking for help to make a complete XPages application of the mail, calendar, and even workspace functions. While I'd love to see that it's a HUGE undertaking. If you are looking for the workspace that has been done in a couple places. One was semi-commercial so probably not free, but I thought someone did do a very basic free version a while back.
For email and calendar you are likely looking for more help then you're going to get for free on this or any forum. You'll be best served in engaging a business partner who can help you with your specific needs. I'm sure there's a cost to that though.
In THEORY, if you have a repeat control that's showing the users email inbox, you should be able to generate a link to open that email in iNotes. You're out of XPages then, but you can get to the email via that existing iNotes interface.