Android :: Capabilities Of Calendar/contacts Apps

I'll be buying and Android phone with Verizon sometime soon. The one issue stopping me at the moment has to do with the capabilities of the calendar/contacts apps, and I'm hoping someone who is familiar with the android OS can give me a workaround (so I can justify buying one sooner rather than later.)

I've been using Palm Treo's for years, and use my phone for running my business, including scheduling clients and making notes about client sessions. With the Treo, and using a third party calendar app (Datebk), I can link someone in my contacts/address book to an appointment. So when I look at my Wednesday 1pm appointment with John Doe, with one click I can go to a list of all appointments I've had with him over the years, and can easily go to any of them and find session notes, etc. It basically links my contacts and calendar so I have access to all the info on that client easily. (The old Palm PIM when was genius).

Is it possible to do anything remotely like this with Android? In the little playing around with Google Calendar, and in playing with the Droid and Eris at the Verizon store, I couldn't see that there's any way to do this, without manually creating a list of session dates for a client every time I make an appointment. I know that the Datebk creators have talked about an Android app coming later in the year, so I may have to wait till that happens. Much as I'd love to upgrade now, I run my business on my phone, and having the capability to handle client/session info in a way I can easily access is near the top of my priority list.