I don't have Lion so I don't know if the facility has been removed: but you may be able to publish a local ('On My Mac') calendar to a web page by control-clicking it and choosing 'Publish'; you will need to enter the settings for your webspace server if you don't have MobileMe.
If you have a MobileMe account and have calendars listed under its login name, then you can't publish those.
If you have iCloud, any local calendars have probably been moved to the iCloud server: you can't publish these, you would have to move any calendar you want to publish back to 'On My Mac' (where of course it can't sync), so you have a choice between publishing and syncing any particular calendar.
To move a Mobileme or iCloud calendar back to 'On My Mac' please follow the second set of numbered instructions on this page:
http://www.wilmut.webspace.virginmedia.com/notes/movecalendars.html
It's written for MobileMe; probably it works the same for iCloud but I haven't been able to verify this.