Great article and fun pictures. I have never seriously tried this, because it takes a LOT of patience ;-)

If growing from seed, it can take anywhere from 5 to 13 years before the tree is mature enough to set fruit. However, trees grown from fruit, usually will not produce fruit at all.

But the truth is, it's much easier to buy a tree from a nursery that has been grafted. At that point it might fruit in 3-4 years. (well worth the cost of the tree)
Grafted trees are sure to produce fruit, because they are grown as a clone of a fruit producing tree; a tree known to produce fruit, and the grafted tree is a genetic copy.

You could theoretically graft your own tree, but it requires precise environmental controls, and will usually fail for most neophytes.

California varieties of avocado only grow well in a Mediterranean climate, which limits them to California's central and south coasts.

Of course it can be a fun project, and it costs nothing, and so for educational purposes, etc, have at it. It will produce an ornamental evergreen that can be very beautiful.