I've stumbled on two good resources recently for Tablet development.
The first is Dr. Neil's Getting Started eBook. For the novice tablet developer this is a terrific first-time resource. On his Samples page you will find a homegrown notepad application and sample code for ink manipulation (loading/saving/clipboard).
The other is an Ink Utility class posted on Rhy Mednick's chickenscratchsoftware.com. The class includes methods for bounding, scaling, positioning and aligning Ink. Read the articles, link to the docs, and download at will.
There are many more of course. The MSDN Tablet Developer Center is a great starting point, as your first download should be the Tablet SDK, and XPSP2 (if you don't have it already) which contains the free upgrade to Windows XP Tablet Edition 2005.
Windows XP Tablet Edition 2005 deserves special mention. Anytime a service pack makes your PC an order of magnitude more enjoyable to work with, well that's gotta be good.
The new Input Panel alone makes this one worthwhile. It's accessible whenever you hover near a textbox, automatically expands to multi-line when you reach the edge of the screen, and has combed input for entering non-words like URLs or e-mail addresses. And it provides instant feedback as you ink, so you know before clicking Insert whether it understands your scrawl. I now find myself using the stylus more while surfing, filling in forms, working in Office apps, anywhere. It's really that good. Together with an improved recognition engine, this is a no-brainer. All that's missing for me is recogniser support for Canadian English. Go get it!