It is simpler than you think.
1) To first order, an ESC simply replaces the throttle servo, so you plug the ESC connector (same as a servo connector) into the throttle channel.
2) Most ESC come with BEC =Battery Eliminator Circuitry. What this means is that the battery for the motor is lowered in voltage to supply the receiver and servos. Most if not all ESC also have a "LVC" =Low Voltage Cutoff", where if the motor battery reaches a defined low value (meaning it is close to being completely discharged in terms of supplying the motor), it turns off the power to the motor. However it keeps supplying power to the receiver and servos. Usually by throttling back to zero, you can re-enable the throttle power in order to limp back to the field. However you shouldn't overdo this, since LVC will be crossed again.
3) The ESC has two wires that plug into the battery. You will need to choose the variety. Personally I use Dean's Ultra for all my e-planes, although I could get away with a smaller connector for less than 10Amp applications. You will need to size the battery to the application.
4) If you are running a brushed motor, you will need a brushed ESC. It will then have two wires that run to the motor wires. You will need to add connectors here too.
5) If you are running a brushless motor ("modern" technology), you will need to use a Brushless ESC. It will have 3 wires going to the 3 wires of the motor. How you hook up the 3 wires doesn't matter. If the motor runs backward, simply switch any two of the 3 wires and it will run the other way.

In both 4&5, you will probably need to add connectors again! I use 3.5mm bullet connectors.

So no diagrams, but I hope this helps.