I'm surprised no one has suggested
books by Francis Chichester or Robin-Knox Johnston. No solo-sailing reading list is complete without these. Also, don't neglect "Alone Through the Roaring Forties" by Vito Dumas. Of all of the books I've read on single-handing, this one is my favorite.
Keep in mind, these books and those by Slocum, Moitessier, the Hiscocks, Smeetons, Graham, etc, are mostly narratives -- stories -- not how-to books or instruction
manuals. Certainly, you can learn from these stories, but eventually you'll have to write your own. There are
manuals, and you should consult them, but the best teacher is experience -- actual time at the
helm. Sometimes, preparation is just procrastination.
I've single-handed thousands of miles. I didn't go crazy like some other posters have warned. My
advice is to keep your
boat simple and to always tether up. Lines led aft just tangle, and you will have go on
deck in bad
weather (it's part of the fun). Get real sleep -- not fifteen minute naps.
Be careful in major lanes, but the odds that you'll be run down on the open ocean are infinitesimally small, so rest up; you'll need it. Nevertheless, trust your
boat and yourself in bad
weather, which happens less than you imagine. Bring books, a journal, and a harmonica for the long periods of boredom. Know how to use a
sextant and to dead-reckon because your
electronics will fail all the way to the
batteries themselves. Maintain your
windvane, your
sails, and your
rigging. Keep your boat and yourself clean. Don't be afraid to go swimming in the calms. Lastly, when you say goodbye to your friends and
family, say it like it's the last time. Your mind will rest easier knowing you've done that. Everything else, you'll learn for yourself. Good luck.