Yes.
In the red cover on the positive terminal of the battery.
Follow the positive battery cable down to the engine. It is bolted to the starter.
It's in the red cover that is connected to the positive terminal of the battery
How to open hood on Toyota echo
See related link.
The Toyota echo does not have wires or a rotor, each spark plug has its own ignition coil (coil pack). So really, all you can do is change the spark plugs.
yes
If you are asking if you can tow with a Toyota echo, the answer is yes. See related link for a video of a Toyota Echo towing a small trailer (and off roading).
1) Open hood 2) Back off bolts holding fastening bar 3) Loosen positive and negative fasteners to battery 4) remove battery
2001 Toyota Echo doesn't have a timing belt.
http://pdftown.com/2000-2002-Toyota-Echo-Service-Manual.html