I haven't tried Tripit but will look at it...sounds interesting.
I use Outlook. I have set up a separate calendar just for travel stuff and I bang in anything that I can't download to it, then I publish that calendar to the web (availble in Outlook 2007 and maybe prior versions) and can also determien whether the people I share with can read only or edit it. Prior to that I used a calendar template in Word, but that took me forever to use.