In episode "The One With The Tea Leaves" (S8E17), the restaurant's door can be seen near to Phoebe's new laundry place. The wall is holding a florist neon sight instead of a restaurant one. This placement shows that the dinner between Chip and Monic took place outside the restaurant, and the neon signs from the records store that can be sighted in the laundry episode is showed behind Chip. Addionally, this neon signs from the records store and florist can be seen in several chapters in front of Central Perk in night scenes, so linking these locations, the Dot's Spot could be in front of the Friends' most famous coffee house.
Dot's Spot can also be seen in "The One With Joey's Porsche" (S6E5), the Porsche parked near the restaurant, but there are no signs of the corner where the Bleeker Street Dry Cleaner Laundry should be. The restaurant next door is numbered "246", and this door is exactly on the top of the car. The same Florist sign is on the wall, and Ross and Rachel find Joey between Dot's Spot and the Record Store previously mentioned.
In "The One Where Ross Dates A Student " (S6E5), Ross' fellow professor, Burt, is seen exiting Dot's Spot.