Parafin wax would normally be in "solution" in white spirit.  How do I
get a "dispersion" (instead of solution) of parafin wax in the white
spirit?  I'm assuming that the white spirit has to be cooled and the
parafin wax is then heated until molten and then added very slowly to
the white spirit with a high shear mixer constantly on in the mixture.
 The wax has to "shock cool" somehow as it comes into contact with the
white spirit.

I have a feeling that there may be some kind of chemical manipulation
which aids this process - perhaps some kind of additive which is added
to the white spirit.

It probably depends a little on what your definition of "dispersion" is.
According to Dorland's Illustrated Medical Dictionary
"dispersion (dis·per·sion) (dis-p?r´zh?n) [L. dispersio]  1. the act
of scattering or separating; the condition of being scattered.  2. the
incorporation of the particles of one substance into the body of
another, comprising solutions, suspensions, and colloid systems."

You can see it used in this sense as a substitute for "solution" even
in technical publications like material safety data sheets e.g. see
http://www.jangro.net/COSHH/LiquidFloorWax%20BD131.pdf

This use is possibly more prevalent where the product is such that the
solvent is intended to evaporate leaving behind the solute, as is the
case of wax applications, but in any case from your question I take
you to mean a suspension.

But strangely, I did almost this exact thing just this afternoon,
making a test batch of a paste wax using carnauba and turpentine.

I got this quite easily by simply cooling a warmed super saturated
solution of melted carnauba in warmed turpentine (hot water warmed,
take the usual precautions around highly flammable solvents). As the
liquid combination cools small particles of wax form a suspension in
the saturated solvent as the solubility falls with the temperature.
The size of the particles would obviously be affected by the rate of
temperature drop, the degree of saturation at maximum temperature,
agitation, etc but in my case it was quite fine with just slow cooling
and an occasional stir.

You don't state how demanding your requirements are or the scale
needed but I suggest some simple experimentation.

Hope this is of some help.

You may be able to disperse the Parafin in water by heating the water
and parafin above the melting point of the parafin. After doing this
add a surfactant (maybe a polymeric surfactant) to create a
parafin/water emulsion. After this you solvent exchange the parafin
into the the minerial spirits.