Here's some of the sources I found:

Introduction to Black Powder Cartridge Reloading

The BP Cartridge Rifle Reloading Guide

Loading BPCR Cartridges

Reloading Black Powder Cartridges
This one is from the people at Starline, who make cases for lots and lots of cartridges.  When they're not sold out of most things as they are now.

Throw in the book I mentioned the other day, Shooting Buffalo Rifles of the Old West.  It covers the history of most of the rifles and cartridges that fit that description, information on general shooting/hunting loads, and a section on putting together match-quallity loads.

There's enough stuff out there on this here innernets to drown in, some good and some not.  A few the the more important things I'll mention:
There CANNOT be any space between the top of the powder column and the bullet base.  Empty space can translate to a ringed chamber or a kaboom.  If a load you want to try doesn't fill that space completely, use wads to fill it up.

You have to use a bullet lube designed for black.  With smokeless powder the lube is to lubricate between the bullet and barrel wall; with black it also has to have enough of a grease content to help keep the fouling soft.

For my cartridge cases the process I've been using is to take a old Lee Hand Press to the range with a universal depriming die installed, and a bottle full of water.  I fire a shot, unload, deprime the case, and drop it in the water.  You don't have to do this right away, soon as you get home is fine, but the sooner the better as it'll keep the fouling from setting up harder.  This way, when I've got 15-20 in, I swirl it around and dump, fresh water, swirl and dump(usually twice), then drain and leave them spread out in the bed of the truck to dry.  When home I use water and a baby bottle nipple brush to clean them out completetly, then dry, then tumble.  
One of the things I get from doing it this way is that it makes me slow down between shots.

If the fouling has gotten tough to remove by the time you get to it, you can add some vinegar to the water and let them soak a few minutes, then brush and rinse.

You will find a blow tube handy.  It's a cartridge case with a big hole bored in the base and a tube stuck in.  Just before you load for the next shot you stick it in the chamber and give a few slow breaths; the moisture helps keep the fouling soft.

With a single-shot cartridge rifle cleaning the bore is easy.  Personal favorite cleaner is Ballistol; one of its intended uses was originally cleaning corrosive primer residue.  Put some of it in a bottle, add ten parts water(I think, the formula is on the can), and shake well before use.  Two or three wet patches through the bore, then one or two dry, and that's it.  I'd give it another shot when you get home(because I'm paranoid about rust), and you can also wipe out the action to get rid of any traces, then dry and oil.

On cleaning, lots of ideas out there.  You can use hot water, with or without a drop or two of dish soap added, if you can find it Windex makes a window cleaner with vinegar, or you can mix something up yourself.

Being now kind of cross-eyed from the day so far, I'm stopping now; if I can think of something else useful I'll add it in later.