Electronics and Controls
It is important to include electronic controls for your home energy system. Electricity coming from the source should be regulated against overcharging your batteries, and your appliances should be guarded from overuse. 

DigiKey stocks just about every electronic and circuit requirement you might have

Regulating your sources can be done in several ways, most commonly, using a charge controller. The charge controller can read when your batteries are full, and subsequently shorts out the source, so that no more power comes in. Then, when the level of the batteries drops a little, the charge controller will switch the source back on. Of course, if the charge controller cuts out the source, there is effectively a bunch of power that is being wasted (not being used). To counteract this, you can use a diversion, or dump, load, which uses up the excess energy when your batteries are full, to power something like a hot water heater or air compressor. 

Manual cut-off switches are essential for safety purposes. If you need to work on any part of the system, it helps to have a way to easily shut off any electricity coming in.

Your system should always be fused between the source and the battery, and also between the battery and the appliance. That way, if something should happen, the fuse will blow, interrupting the circuit, and your components will remain unharmed. Fuse your system as close to the batteries as possible.

You will also want a voltage meter to check the state of your batteries, and an ammeter on each source to show how many amps your source is generating.  Proper system health can be achieved with the proper controls, regulators, and metering.

Additional Resources:

• Fieldlines  and OtherPower - The best home-power resources on the web
• Red Rock Energy - Good information including circuit diagrams for controls and even solar tracking
• Solatron Technologies - A great source for components
• Charge Controller Kit and Information