"how do you prepare and deal for heavy weather sailing (or worse weather than you have ever seen) without the experience of having encountered it?"
Well, if you work your way up to it by going out in worsening wx with mentors aboard--that doesn't count since you are encountering it.
There are only two known ways that human beings pass on knowledge to each other: Speech and writing. So, you pick brains, attend lectures, and READ UP. The local library won't have any of the classic sailing books (if they did have them, they've long since been stolen) but at least with the web you can buy them secondhand.
Reading up won't give you the muscle-memory of what to do, or how to tie reefing lines without looking at them, but it gives you the chance to train for that. Reading up will give you the concept that everything that isn't secured, WILL LAUNCH AS A MISSLE and that includes your ribs getting smashed into a table or counter corner.
Reading up won't teach you "Yeah, I think it is time to reef now" but it will make you aware that you're better off reefing BEFORE you think you need it, and developing a firm policy like "When the wind speed reaches 16 knots and is building, WE REEF NOW."
So, I'm a big fan of reading up. Somewhere there's a thread of classics. Coles on Heavy Weather, Fastnet Force 10 to see what kind of judgement errors even experieneced sailors are fooled into ...
And one other thing you may or may not find mentioned. Even if you have rock-steady nerves, if you think the wx is really going to stink, think about taking seasickness meds a good hour BEFORE that weather hits. Try the meds at home, on a wekeend, when you can always sleep it or or get help if you react badly. Look at the serious meds--like scop and compazine--as well as the electric releif bands and the OTC meds. If you do one per weekend, or two per month, that can still take 3-4 months to check out. You'll find one works well for you, one is useless, a third puts you to sleep and is worse than useless.
There's nothing like working up to it with a trusted mentor--but so many great authors have witten so many good books, that you should be able to cut a lot off the learning curve (and enjoy some good reading) going through a pile of classic used books, too.