Why?
My point is not to drag this out (but not to act creepy) – after a date with someone you like, say “this was nice, I’d like to see you again – can I call you?”. If she says “yes”, call in a few days and ask for another date, and if she demurs then assume that’s rejection. If she says “no”, then that’s rejection. If she agrees to another date then that’s not rejection. So there’s zero (or very little period) in which there’s a chance at false hope.
Expend the effort on those who make it clear they’re interested, in other words.
Acquire one. Go out and make a boatload of cash. Pump yourself up at the gym. Learn ancient Greek. Get good at chess. Memorize the Catalogue of Ships from Homer. Learn some chords on the guitar. Be good at your job. Take up cooking. Whatever. Just, for fuck’s sake, accomplish something.
Do something that makes you feel like you’re the kind of guy that the women that you like would be attracted to. Then come back, bring pie.
(If that’s tough love, I’m sorry. But telling you to keep doing the same thing and expecting different results probably isn’t good advice either.)
If you already have accomplished things that make you feel good about yourself, then maybe you’re good to go, and you’re just having hard luck, and just a change in posture will do the trick. Or maybe you just need to accomplish some more stuff.
On being confident: here’s a suggestion—take it for what it’s worth:
Either take a skill or ability that you already have, or learn a new one, and get good at it. The feeling of competence and confidence that you get from being good at something will, hopefully, carry over to a more general attitude of confidence.
Bonus points if the skill is something that could directly attract women, like (say) playing a musical instrument.
I would have suggested electric guitar (it’s a more ‘modern’ instrument) - except that perhaps *too *many men have gone down the guitar route of late.
See, if I knew the guy socially but not very well (i.e., not well enough to have thought of him as a possible date), I’d find “if you’re not interested let’s never speak of this again” hilarious, and might go out with him because of it.
But I’m not the norm, so take anything I say with a grain of salt.
Guitar didn’t work for me a jillion years ago. It doesn’t hurt, but no woman ever seemed that impressed.
Are you actually being serious, OP?
It sounds like you’ve already given up on yourself. Don’t do that!
Have you tried online dating? I am a introvert to top all introverts and I successfully met two wonderful men (one now deceased) online. Please don’t go the grade school passing notes, route. Give yourself a decent chance.
Take up the guitar?
How about be reasonably successful in whatever you’re doing for a living. Have a sense of humor. Don’t stink. Look as decent as you can. Be friendly. Be nice. What’s so hard?
Ok, I’m old. But my kids are in their early 30’s and they didn’t have a hard time finding dates/mates. WTF is going on here, folks? What changed since my youth that’s made this so difficult? Educate me.
Jim, a guy as bright as you should have no problem with the opposite sex. I have a feeling you have a faulty strategy somewhere. I am not good looking or particularly bright, I am short and bald and I doubt I have ever gone 2 weeks in my life without getting laid . Be positive up beat and honest and just be yourself.
Look, this is the old “It worked in this case, so why not in your case” line. Everyone’s different.
Always easy to lecture people who are not yet over the hump when you’re over the hump. I’m not being snippy; just saying.
Don’t ever say that again!
How does in person rejection work exactly that is so unconfortable?
If you ask someone out and they say they have laundry to do and don’t offer any alternative plans or show any interest, then that’s rejection. Just play it off and move on.
It’s hard for me to imagine how this is more awkward and painful than an ignored email.
Things that come easily to some people don’t come so easily to others. That goes for math, foreign languages, dancing, staying thin, saving money, managing time—and dating (not to mention other aspects of human interaction).
Bolded for emphasis.
Anyway, from an old fart, just go out and meet people. Be yourself no matter what venue.
You will meet people that you will never want be around again no matter what, and that you will meet folks that will become life-long friends…and guess what? You met someone through friends or acquaintances who is interested in you and maybe you them.
Getting a date for the first-time or second-time isn’t the point of a future relationship.
Getting to know someone is more important.
Gah…hope you know what I mean. 
But this is ridiculous, bordering on weird. There used to not be dating websites and such. There was school, work, church, and the corner bar. You guys are making this harder on yourself than you have to.
You could try my younger brother’s technique when he was a teen. He’d call a girl up and say “Uhhh…you wouldn’t want to go out with me, would you?” Often enough, they agreed.
Look for someone you find exciting in person. It could take awhile, so wait for it. Only ask out the person you most want to date- within 100 miles or more. If you get rejected, mope for awhile, cross 'em off the list, rinse and repeat. You don’t have to fake confidence; you be brave and go for who you genuinely want, exclusively.
How do you deal with it if you run into them again? Just pretend it never happened? I think I’d have a hard time refraining from saying, “So…we’re still not talking about it, right?” 
I think I’d also find it just off-putting that someone’s basically trying to control how I respond. It comes off…well, controlling!
This is exactly what I’ve done. I have no interest in dating women who are nearly complete strangers. I want to know enough about them to know that I have at least some basis for getting along. I like smart women and funny women, and to know that they are this I have to observe and interact with them for a while.
These are the women who reject me.