second on William Nealy's book. both the original
and the new version
are both great reads, and good additions to any book collection.
my advice is to simply go look at water. go find a river/creek/irrigation ditch and sit by it and just watch. watch how the water reacts to obstructions in the river, watch how it pillows off of walls, watch how it creates tounges, eddylines, waves and holes. look at different stretches of water, from class II gravel bars, to raging class V rapids. note the differences that small variations in the riverbed make. the beautiful thing about hydrology is that it replicates itself on a small scale to a large scale. the way water acts and reacts to things on a ditch with 25 cfs in it is no different than how a river with 2500 or 25,000 cfs reacts; it's just bigger and more powerful. the basic processes are the same.
spend time noting features, and how they work. once your understand how the river works, it makes reading it ON the river much easier. knowledge is power