This is the instructions to obtain your Google ICAL web address. See here for Yahoo Calendar ICAL or for other sources see here to import ICAL / ICS / iCalendar data.
1) Log into your Google Calendar account.
2) On the left side you will see 'My Calendar'... For the calendar that you would like to import, click the 3 dots next to it (on mouse hover) and then select 'Settings and sharing' ...
3) In the resulting screen scroll down to where it says Secret address in iCal format. Tip: use Ctrl-F and search on Secret to easily find.
4) Upon selecting 'Insert WinCalendar' in Word or Excel, click in the 'Setup...' button next to the 'Import Google Calendar Data' Option & paste in the above address.
Note if your PC does not have internet access you can also import Google Calendar ICAL data by saving the ICAL file to your a local drive & then instead entering the file full name (ie: c:\PathToFile\myIcalData.ics) into the WinCalendar form.