Hi-
And please stick with one thread--posting virtually identical posts under different categories does nothing other than increase the likelihood that you won't get meaningful responses (if any).
Off the top of my head, it would appear that you might well need:
1) tblContacts - List of contractors, suppliers, etc.
2) tblProjects - List of projects with start and enddates, with a join table to tblContacts.
3) tblAppointments - List of specific occupied timeframes, tied to tblProjects, tblContacts & tblEquipment.
4) tblEquipment - Equipment you have that may be used in projects and on specific dates, tied to tblAppointments and perhaps tblProjects.
5) tblDiary - Just because you want it.
Shouldn't get 'wrapped around the axle' with the gee-whiz calendar control. It may look spiffy, but more often than not (as in the Appointments application, where it does nothing) it's of limited value.
As Pat pointed here in another of your threads, you should initially try expanding on the application you've found. You could also consider a main form with a multi-page tab control, with each tab addressing one of the area described above.
At this stage, more important than the form(s) is determining what tables you need and getting them setup.
Please post back with your progress (I don't think anyone's going to do the work for you and the chances of finding a template application that wholly meets all of your needs is somewhere between slim and none.)
Best Wishes - Bob