Yep, all of 'em.
Bulbasaur - Where Jynx usually is, but the house is an orphanage and if Pikachu's Affection Level is at a certain point, she'll happily give you the Grass-type.
Charmander - The guy north of Nugget Bridge, you can't miss him.
Squirtle - A bit more of a pain, for the difference is you can't get Squirtle right when you enter the area. You need the Thunderbadge to persuade the Constable that raising the aquatic hoodlum is a good idea.
Pokemon Yellow remains legendary for legitimately earning all three starters, on top of having Pikachu and finding Eevee.