I think it's great when anyone wants to explore the harpsichord! It's a wonderful instrument when it comes to baroque and early music. I, too, would strongly recommend a teacher, but it sounds like that's not an option. Lacking that, I'd listen to a LOT of good recordings if you can (let me know if you'd like a few suggestions), and often the introductions to good music editions will have instructions on how to play ornaments and things. The biggest thing you'll lack, though, is a unifying understanding of the overall "language" - which is important as it's entirely different than piano-playing. Touch can be tricky, too, as well as tuning, which is CRITICAL. Do you have a good tuning machine? Do you have a good ear? Can you hear beats when you play an interval, or a unison that's out of tune? Do you have access to anyone who can help you learn how to tune this instrument? THis is probably the trickiest thing to do on your own (I'm not exactly sure it can be done entirely on your own... but it's worth a shot. I could offer a little guidance if you want to try...)
Tuning is actually one of the most rewarding things, I think, about listening to, and playing the harpsichord, and essential to the beauty of the music, in my opinion.
Well. Don't know if any of that helps, but excited you're giving it a try!

JH