Not really many of them around nowadays, Edinburgh (as far as I know) is very quiet.
You'll be lucky to find any out and about, not that there is none, just very few and far between.
Some nights you might come up with zero.
Like many places (in Scotland) they are a dying breed.
So if you drive around leith links (park) you might find one or two.
Some have already mentioned the streets but here are a few...
Salamander Street and Johns place as already mentioned. (just confirming the activity there)
Salamander place and Links place (especially at the corner between the two, or at least used to be activity there).
Duncan place (this leads on to Johns place).
Links gardens, Gladstone place, Claremont park (joins with Salamander street)
Thats the general condensed area now. Don't know if there is anything outwith this area, perhaps someone may enlighten us?