Parking all over town is free. If you are lucky you can nab on on the town square (area 1) but if its full (usually full from 7 PM onwards) there are lots of options in easy walking distance.
That one lot (Area 6) at the lower left of the picture has been a good bet recently and almost always has a spot. Walk in that lot towards the house and there is a staircase that drops you right by the pizza place.
Around 6 PM onwards the spots start to fill up as people get home from work.
Lot 2 and 3 are hit and miss but also tend to fill up from 6 PM onwards. Area 4 always seems full, I no longer even look.
Area marked as 5 is last resort. It is a heck of an uphill hike through the oldest part of town (yellow circled area) but I actually like the climb.
Yorktown 1750
1 Pl. de la Tour, 06620 Le Bar-sur-Loup, France