A list (aka "tabular") or Agenda view of all events (appointments, tasks) would sure help -- but Apple removed that feature in 10.5. (I blame Apple's penchant for doing insanely stupid things like this for the tooth I broke yesterday.)
There is a workarounds ...
Macworld | Mac OS X Hints | View all events in 10.5’s iCalA single double quote (") character also works.
While iCal in OS X 10.5 has some nice changes—default event alarms, for instance—there are other changes that weren’t so nice (the loss of the sidebar with its easy-to-use event info still bothers me a lot). Another not-so-welcome change lies in the ability to view all of your events (and/or to dos) in a nice list view. In the 10.4 version of iCal, clicking a list-view-like button on the lower right of the iCal window would bring up a pane showing all your events. That button—and seemingly, the ability to see all your events—is gone in the 10.5 version of iCal.However, there’s a strange workaround that will create a similar view—why it works, however, isn’t clear to me. To see a list of all your events and to dos, simply type a period (.) in the Search box at the top right of the iCal window.
You can also view iCal events using the Finder's cover flow feature, but that's not a terribly useful feature. It is good to remember that kind:ical will find all iCal events.
From the search/list view you can delete events or select and move them to a specific calendar.
PS. Operations performed on multiple items from the search view are exquisitely slow. They bring my PPC machine to a standstill. It helps to kill the 'mds' (spotlight) process.
Update: After an extended bout of iCal editing I killed my PPC session in a unique fashion. The screen blacked out. I had to hard cycle. There are ugly bugs in iCal!