You can post the link in a Google Calendar event's Description field, of course. To open the document you — and all invitees — have to copy and paste the URL, though, instead of just clicking.
How much more convenient would it be to attach Google Docs documents instead, with an automatic and appropriately named link?
Link Google Docs Files With Google Calendar Events Easily
To attach a Google Docs spreadsheet, document or presentation to an event in Google Calendar:
- Make sure Attach Google Docs is enabled (see below).
- Select Create Event (hit c) to add a new or double-click an existing event.
- Click Add a Google document or Add another Google document under Attachment.
- Check all documents you want to associate with the event.
- Click Select.
- If you share the calendar or event with others and want them to be able to view or edit the attached document:
- Click the document under Attachment.
- Select Share | Invite People... in Google Docs.
- Enter the desired email addresses under Invite:.
- Make sure To view is selected if you do not want to grant editing powers; otherwise, select To edit.
- Click Add without sending invitation to share the document immediately (usually preferable for documents attached to Google Calendar events); click Send to send an invitation instead.
- Click OK if you decided to forego the invitation.
- For multiple attached files, either repeat the process for each or go to Google Docs, check the shared documents and select Share from the toolbar.
To open or remove an attached document in Google Calendar:
- Click the event in the calendar or agenda.
- Follow the edit event details» link.
- Click the desired document under Attachment to open it.
- Click remove next to an unwanted document to remove it.
- The file will not be deleted from Google Docs, only from the event.
Enable "Attach Google Docs" in Google Calendar
To add easy Attach Google Docs links in Google Calendar:
- Follow the Settings link in Google Calendar.
- Go to the Labs tab.
- Make sure Enable is selected under Attach Google Docs.
- Click Save.