I would say the quickest way to learn the mechanical side of things is to grab the manual and work on the little Datsun, you will be an expert in no time and feel a great sense of satisfaction.

I am sure many of the guys here know everything they do because they couldnt afford a mechanic and had to try it for themselves.

Datsuns are the easiest cars in the world to work on, you will surprise yourself.

If you dont have any tools, get a chinese kit from Bunnings or Supercheap for $100 or so, they will work fine,I am still using the tools I bought at KMart 18 years ago.

Where are you located? there might even be someone from the site local to you who could pop in to show you the basics.