The dots were traditionally made with a school compass or other sharp implement and ink poured into the hole. Tattoo artists are an option for those talented enough to have managed to steal a few quid from a granny.
They are worn by particularly brain dead and tragic denizens of Portsmouth (aka Pompey) - a depressing town on the South coast of England.
Owners of Pompey dots are very likely in-bred, doubtless mentally deficient, and definitely chavs. They should be considered dangerous, and certainly chlamydia carriers. Avoid them at all costs.
Y'up fa Route 66 t'night?*"
*The age gap between generations of Portsmouth families is usually around 13 years. Accordingly, 3 generations of Portsmouth slappers are regularly seen dancing together around piles of handbags in local night clubs.