Church Windows - Web based and hosted management software for churches
MakePlans - Online appointment booking - MakePlans
Touchpoint - Touchpoint is the all-in-one customer engagement software that connects your sales, support, and marketing activities across multiple channels
Appointment Booking Calendar - With the Appointment Booking Calendar you can accept online bookings from a set of available time-slots in the calendar.
IconCMO - Church Management Software. Simple to Use. Power to Grow.
Dudle - Dudle is an online scheduling application, which is free and open source.