To sync your VanillaSoft calendar with your OutLook calendar you must work in conjunction with a Google Calendar.
For this you will need to sign up for Google Apps for Business for $5/mo or $50/yr in order to get access to Calendar Sync between Google and OutLook.
Details can be found at the following links:
http://www.google.com/enterprise/apps/business/pricing.html and https://tools.google.com/dlpage/gappssync.
Once you get your Google calendar to sync with your OutLook you may then set up your Google sync with VanillaSoft by following the instructions here: