For the most part, I break yeast into the following mjor categories:
From there each one may have 5 to 50 yeast strains that add subtle chracter differences.
My advice would be to brew a recipe with a base malt bill (keep it simple, and possibly low in roast and hops to let the yeast shine through) and then toss in a yeast from the major types and see what you get.
Once you decide on a beer style you like, brew it a few times with many different sub yeast strains. (wlp001, wyeast 1056, WLP 090, denny's favorite (wyeast), US-05, California V, cream ale blend, american ale blend....and find the strain that does what you want. (these are just a few of the american ale strains)
THen take that strain and put it into different enviornments... 65, 70, 75 F extra O2, no O2, Air only, O2 only, ferment in Carboy, ferment in buckets...
And then write a book called YEAST II... :-)
What I have been doing is taking 5 gallons and fermenting in 5 1 gallon jugs. I have found I love Mexican Lager Yeast from Whitelabs for lagers. It is clean, low sulfer, quick to ferment, flocks well,and both the malt and hops are "bright and distinctive" compared to WLP830 and WLP 833.
Essentially, there are a ton of yeasts to try, and a lot of different ways to use them. Just make sure your experiments change a single variable in each one, and you will learn a lot. Reading is no substitute for experiance)