You would get a better response in the Exchange forum but to quickly point you in the right direction, you can export your calender to CSV then import into SQL. You can do this using either BCP or DTS. If you find you do want to do it that way, Im sure there is a BCP faq on here.
There are tools out there that will assist you doing this without BCP/DTS, a quick google reveals.
In the meantime, I would post in the appropriate forum for a meatier response.
"There are only two lasting bequests we can hope to give our children; one of these is roots, the other wings" - Hodding Carter