Special thanks to Ren Dragi for helping me with the list.
001:Bulbasaur-Route 1
002:Ivysaur-Evolve
003:Venusaur-Evolve
004:Charmander-Route 1
005:Charmeleon-Evolve
006:Charizard-Evolve
007
quirtle-Route 1
008:Wartortle-Evolve
009:Blastoise-Evolve
010:Caterpie-Route 2
011:Metapod-Viridian Forest
012:Butterfree-Evolve
013:Weedle-Viridian Forest
014:Kakuna-Viridian Forest
015:Beedrill-Evolve
016
idgey-Route 1
017
idgeotto-Route 12
018
idgeot-Evolve
019:Rattata-Route 1
020:Raticate-Pokémon Mansion
021
pearow-Route 11
022:Fearow-Kindle Road
023:Ekans-Route 22
024:Arbok-Route 23
025
ikachu-Viridian Forest
026:Raichu-Thunder Stone
027
andshrew-Route 4
028
andslash-Route 23
029:Nidoran?-Route 3
030:Nidorina-Safari Zone
031:Nidoqueen-Moon Stone
032:Nidoran?-Safari Zone
033:Nidorino-Safari Zone
034:Nidoking-Moon Stone
035:Clefairy-Mt. Moon
036:Clefable-Moon Stone
037:Vulpix-Route 8
038:Ninetales-Fire Stone
039:Jigglypuff-Mt. Moon
040:Wigglytuff-Moon Stone
041:Zubat-Mt. Moon
042:Golbat-Seafoam Islands
043:Oddish-Route 24
044:Gloom-Route 13
045:Vileplume-Leaf Stone
046
aras-Mt. Moon & Safari Zone
047
arasect-Safari Zone
048:Venonat-Route 12
049:Venomoth-Safari Zone
050
iglett-Diglett's Cave
051
ugtrio-Diglett's Cave
052:Meowth-Route 5
053
ersian-Kindle Road
054
syduck-Route 8
055:Golduck-Evolve
056:Mankey-Route 22
057
rimeape-Victory Road
058:Growlithe-Route 8
059:Arcanine-Fire Stone
060
oliwag-Cape Brink
061
oliwhirl-Evolve
062
oliwrath-Water Stone
063:Abra-Route 25
064:Kadabra-Evolve
065:Alakazam-Evolve
066:Machop-Rock Tunnel
067:Machoke-Mt. Ember
068:Machamp-Evolve
069:Bellsprout-Route 25
070:Weepinbell-Island Two
071:Victreebel-Leaf Stone
072:Tentacool-Route 21
073:Tentacruel-Island 1
074:Geodude-Mt. Moon
075:Graveler-Cerulean Cave
076:Golem-Evolve
077
onyta-Mt. Ember
078:Rapidash-Mt. Ember
079
lowpoke-Safari Zone
080
lowbro-Seafoam Islands
081:Magnemite-Power Plant
082:Magneton-Power Plant
083:Farfetch'd-Trade with Elyssa
084
oduo-Route 16
085
odrio-Safari Zone
086
eel-Trade with Garett
087
ewgong-Island Four
088:Grimer-Pokémon Mansion
089:Muk-Pokémon Mansion
090
hellder-Route 25
091:Cloyster-Water Stone
092:Gastly-Pokémon Tower
093:Haunter-Pokémon Tower
094:Gengar-Evolve
095:Onix-Rock Tunnel
096
rowzee-Route 11
097:Hypno-Evolve
098:Krabby-Seafoam Islands
099:Kingler-Evolve
100:Voltorb-Route 10
101:Electrode-Power Plant
102:Exeggcute-Safari Zone
103:Exeggutor-Leaf Stone
104:Cubone-Pokémon Tower
105:Marowak-Victory Road
106:Hitmonlee-Route 5
107:Hitmonchan-Route 6
108:Lickitung-Trade with Haden
109:Koffing-Pokémon Mansion
110:Weezing-Evolve
111:Rhyhorn-Safari Zone
112:Rhydon-Evolve
113:Chansey-Safari Zone
114:Tangela-Route 21
115:Kangaskhan-Safari Zone
116:Horsea-Cinnabar Island
117
eadra-Evolve
118:Goldeen-Safari Zone
119
eaking-Evolve
120
taryu-Cinnabar Island
121
tarmie-Water Stone
122:Mr. Mime-Trade with Reyley
123
cyther-Safari Zone
124:Jynx-Trade with Dontae
125:Electabuzz-Power Plant
126:Magmar-Mt. Ember
127
insir-Safari Zone
128:Tauros-Safari Zone
129:Magikarp-Vermilion City
130:Gyarados-Evolve
131:Lapras-Silph Co.
132
itto-Route 15
133:Eevee-Celadon City
134:Vaporeon-Egg/Water Stone
135:Jolteon-Egg/Thunder Stone
136:Flareon-Egg/Fire Stone
137
orygon-Celadon City
138:Omanyte-Mt. Moon
139:Omastar-Evolve
140:Kabuto-Mt. Moon
141:Kabutops-Evolve
142:Aerodactyl-Mt. Moon
143
norlax-Route 12 & 16
144:Articuno-Seafoam Islands
145:Zapdos-Power Plant
146:Moltres-Mt. Ember
147
ratini-Safari Zone
148
ragonair-Safari Zone
149
ragonite-Evolve
150:Mewtwo-Cerulean Cave
151:Mew-Cerulean Cave