It sounds really nice but it isn't readily available as far as I know. Unless it can be extracted effectively from olive leaves (russian olive maybe?) or the oil, or is available as a cheap supplement.. it is a bit useless, no?

yeah, considering that the condensation of acetone with vanillin (Sciencemadness - 1 and 2 + references mentioned therein) will give the saturated precursor to Zingerone. Work out how to reduce the double-bond selectively (or non-selectively - raney alloy in aqueous alkali then oxidise the secondary alcohol to the ketone), then a haloform reaction on the methyl ketone will give the 4-hydroxy-3-methoxyphenylacetic acid.

If condensation were carried out with MEK instead of acetone (in an acidic environment), then you'd end up with with the a-methyl cinnamic acid after the haloform reaction. Forming the amide of that, before or after replacing the methyl group with a benzodioxole group, would give the x-2-aminopropane when reacted with hypochlorite. There are refs for every one of these reactions

"The olives, leaves, and olive pulp contain high amounts of Hydroxytrytosol (compared to olive oil), most of which can be recovered to produce hydroxytyrosol extracts.

One assumes the Wikipedians are taking creative/artistic liberty with their application of the terms "large amounts" and "much of which"? 

Here is a write up (in German - some idea on the relative yields of the products would be great) of a variant of the twodogs/bio/Bogart & Davidson (see above reference - and others) condensation procedure using H2SO4 as the acid catalyst. I've seen reports (elsewhere) that other acids have been used. The reason being is that alkoxy and dialkoxybenzaldehydes are reported to be a little touchy with the hydrohalic acid catalysis (ether cleavage followed by christ knows what - one such report is by Mr Buck of the amines related to 2,5-dimethoxyphenethylamine series, so it is credible). The reduction of the a-methylcinnamic acid and the 3,4-dimethoxy-a-methylcinnamic acid to the hydrocinnamic acids using Raney Alloy with Aqueous alkali is given in the paper by Schrecker (attached)