Things to have:

• Assorted screw drivers (the computer sets are nice, but really just a flat head and a
• Phillips is enough to start, they’re all we used for this)
• A knife (just in case)
• Blue masking tape (to tape down screws)
• A sharpie (to label the blue tape, if needed)
• A camera (so you know where things went)
• Small led flash light (makes part numbers easier to read)
• Canned Air

Once you want to start seeing what does or does not work, rather than just an anatomy lesson add:

• A fused multimeter
• Internet access to look up part numbers

Super Basic safety:

• Be unplugged. (Not having things plugged into the wall is obvious, but remove internal batteries, put switches in the off position and drain large capacitors after everytime you've exposed them to more power.)
• Check that all switches are in the off position.
• DO NOT touch large capacitors.
• Wear safety glasses if you are prying anything apart. (TIP: if you are near sighted, you’ll want to be wearing your glasses anyway to make reading part numbers easier)
• Wearing rubber soled shoes never hurts.

Unknown Parts

Getting

• If you are going to take on a more radical parts harvesting than we’re doing here , i.e. desoldering individual items to use in a different circuit, be really really careful about fumes.  Solder has a number of chemicals that are incredibly harmful to breathe, so, bare minimum, have a fan and a window open, please. Here is an Instructable on just that: http://www.instructables.com/id/Recycle-old-PCB-components/ 

Using

• Confirm values as best you can as you go. Parts may have been abused and no longer function at their labled capabilites (if they ever did)
• Power Ratings matter, don't use a switch that was attached to a small microcontroller to control a large motor, etc.