T.C. Albert's book is great, and is probably the best single resource out there. Another book that is well worth looking at is Stohlman's The Art of Handsewing Leather - Stohlman was the late Chuck Burrow's invariable recommendation for a resource on general leather working.
As for patterns, Madison Grant's article in Bucksinning III has a couple unscaled diagrams, and Steve Lalioff's article in Buckskinning VI and LaCrosse's The Frontier Rifleman contain scaled drawings that could be made into patterns. For a simple pouch, though, it is quite easy to come up with your own pattern. Usually I make a dummy out of paper stapled together to test the pattern before cutting into leather, and I've been known to do a trial run using denim from recycled pants as well. Only real problem is figuring out how much extra to allow for the stitching.