I faint easily and get dizzy spells in which my heart starts racing and I feel/hear the pulse in my neck, but regular consumption of salt seems to keep it under control. I don't know if salt would help in your case; I used to put my dizziness and fainting down to something harmless to do with low blood pressure, but I've started to wonder if it's caused by an ion channel mutation or whatever it is that's affecting me more generally.
Hypothetically worth a shot. I know my blood pressure is low (healthy-low, but, low). I also crave salt/salty foods a lot but I'm not sure that actually means I have a deficiency (unless I also have a chocolate deficiency).
Any suggestions (or links to web sites with guidelines) on 1) how much one should try to add (even to experiment and see if it helps) and 2) how to make this palatable? Not sure I can just sit and eat spoonfuls of salt. 
It's not something I've read about anywhere, so I can't direct you to a site about it. My diet has very little processed food in it, so there's little or no salt in it unless I add some. I was getting very frequent dizzy spells a few years ago and I wondered if it could have something to do with the lack of salt in my diet, so I started salting my food and the dizzy spells went away. I let my body guide me and I just add however much salt tastes good. I don't go crazy with heaps of salt; if I take too much, I get thirsty and start drinking and pissing a lot, and I can wake up several times in a night with a full bladder and feeling dehydrated until my body excretes the excess sodium. If I stop adding salt to my food, I begin having dizzy spells again after a week or two.
Also, magnesium supplementation decreases my salt craving, and I haven't had any dizzy spells from my reduced salt intake while taking magnesium. It has some unusual effects on me; it makes me more alert and energetic, causes insomnia, and makes my masseters tense up, which gives me headaches; pretty much the exact opposite of what it's supposed to do (think epsom salts). I've no idea if you'd find magnesium helpful or not; it can be bought as pills, but I find it cheaper to use a big bag of magnesium oxide powder that was sold as a feed additive for horses.
