As a fairly new bp shooter, the most common thing I read is that substitutes, except for maybe Triple 7, are not highly regarded. From my shooting, substitutes are no less corrosive than real black powder. I was looking for a powder that didn't require cleaning that same day, but it seems that's there is no way around it. If you want a powder that requires less maintenance, you're SOL.
As for power and accuracy, by all accounts I've read, the substitutes have higher velocities, yet bp has better groupings.
And then there's this strange powder called Swiss that, legend says, has the accuracy of black powder with the higher velocities of a substitute. Of course, these are just tall tales as I've never seen such a powder called Swiss on sale at any gun store I've been to.
For flintlock pistols, I would follow others advice here and stick to original bp. That's what they were using back in the day. For percussion, substitutes are fine as they've been proven reliable over many years.
As for the 2F or 3F debate, my rule is if it's a pistol, use 3F, if it's a long gun over .45, use 2F. I use this rule because I'm not big into bp long guns and I don't want to be inundated with a ton of different powders, grain sizes, etc. Honestly, there's nothing wrong with just using 3F for everything and trying out the different powder choices in 3F to see which gives you the best performance. I'd imagine that if you found the Fountain of Youth, there would be a container of that mythical 3F Swiss powder and it would give you sub MOA groups at 100 yards.
As for books, I've been looking up on amazon for some to give to a friend to try and get him into black powder shooting. Here's what I've found lately:
http://www.amazon.com/Percussion-Pi...976&sr=8-4&keywords=black+powder+pistol+books
This is an old, old book, but it's from a well known author:
http://www.amazon.com/Black-Powder-...47208926&sr=8-1&keywords=black+powder+handgun
This one is newest, will have the most up to date info possible:
http://www.amazon.com/Handbook-Mode...6&sr=8-1&keywords=modern+percussion+revolvers