Re: calendar in ad
Hi amoonart and welcome to the forum. At the moment, with Adwords, I'd say the answer is a "no". I can't be 100% certain since I've never come across this sort of request before but I'll base my advice upon the fact that each and every Ad shown has to go through an approval process before being shown. As such your Ad could never be "live", at best it would be a few hours out of date. More importantly, you can't actually change an Ad; when edits are made to an Ad, although it looks like it's being edited, it's actually deleted and a new one created with the edits. So, if you were able to create your calendar, say, every hour or so, you'd never be able to store any performance data, nor gain the advantage of long term CTR/Conversion history.
My best advice would be to make sure your availabilty is shown clearly on your landing page - and that it's easy to use. Oh, and you may find my recent blog (moan) about third-party booking engines useful.