The Park "blue book" is my go-to bicycle maintenance book. It seems to tread the fine line between gruesome detail (e.g., Barnetts) and being overly simplistic. It's approach to problems are very practical and it matches up nicely with Parks online information. Park tools are sometimes a little flimsy but they get the job done.
If you already have basic hand tools, my advice would be to NOT buy a standard bicycle toolkit as it will likely just duplicate a lot of what you have and will probably include tools that don't match up to your bike. Instead, I'd just set to wrenching and when you run into a problem that requires a special tool, go get it. (I'm fortunate in that I have a good bicycle shop nearby that has a good selection of tools in stock and they're not terribly expensive. They also are pretty good about doing repairs on the spot for stuff I don't have the tools for - for example, I don't have the tools for headset installation/removal, but if I take the frame/fork in ready to use the tool, they'll bash it in/out in seconds while I wait and usually don't bother charging me. Nuturing a good relationship with the wrenches at your local shop is a good thing!! There are a lot of things with bicycles that are ridiculously simple with the right tools and an absolute nightmare without.)
Here are the common things you'll likely need fairly soon:
1. Spoke wrench(s). I like the colored Park ones and have all three. You want to be absolutely sure you have one that fits TIGHT on the spoke nipple flats - if it doesn't require a little work to get the wrench around the nipple, you likely are using the wrong wrench.
2. Cone wrenches. Thin wrenches for adjusting wheel bearings. The sizes vary between hubs a bit so you need several. (Adjusting wheel bearings is a bit tricky - be sure you understand what is going on here - simply "backing off" a 1/4 turn like a car wheel bearing doesn't cut it.)
3. Chain-breaker tool. You can sometimes get by with the cheapie universal ones in bicycle multi-tools, but I like having a good shop tool for this.
4. Freewheel/cassette removal tool. This is something that you need specific for what you have on the rear of your bike. And if you have a modern cassette system, you'll also need a chain whip to hold the cluster while you remove the lockring.
5. Inch-lb torque wrench. Lots of light-duty torquing required on bikes.
6. Bottom bracket/crank removal tool(s). Another case where each system has its own special tool(s) for removal.
7. Cable cutter. It's almost impossible to make good clean cuts of cables and housings without a special tool.
8. Chainring nut wrench. Chainrings bolts use a strange nut on the backside that most of the time doesn't turn when you remove the bolt, but sometimes does and unless you have this cheap wrench, to hold this nut, getting the bolts out is very difficult.
That's all I can think of, but as I said, I think you should just dive in and get them as you go.
bikeforums.net has a pretty good section on bicycle mechanics, but like all forums there are some "my way or the highway" blowhards over there so you have to take everything with a little common sense.
Just ran across this the other day and it is a good resource for understanding parts, compatability, etc.
I find bicycle mechanics a lot more approachable that motorcycle mechanics. More art than science. I recently did my first wheel-build and it was great fun.