Starting Area:
* Tweedle: Route 201
* Starly: Route 201
* Bidoof: Route 201
* Kricketot: Route 201
* Shroomish: Route 201
* Pachirisu: Route 201
Eterna Forest:
* Budew: Eterna Forest
* Buneary: Eterna Forest
* Cherubi: Eterna Forest
* Chingling: Eterna Forest
* Snover: Eterna Forest
Route 202:
* Chimchar: (Starter)
* Piplup: (Starter)
* Turtwig: (Starter)
* Geodude: Route 202
* Ponyta: Route 202 (Rare)
* Aipom: Route 202
Route 203:
* Machop: Route 203
* Shellos (West Sea Form): Route 203
* Omanyte: Route 203 (Fossil)
* Kabuto: Route 203 (Fossil)
Route 204:
* Zubat: Route 204
* Golbat: Route 204 (Rare)
* Mothim: Route 204 (Evolves from Burmy)
* Burmy: Route 204
Route 205:
* Pidgey: Route 205
* Pidgeotto: Route 205 (Rare)
* Staravia: Route 205
* Staryu: Route 205
* Starmie: Route 205 (Rare)
* Gible: Route 205 (Rare)
Route 206:
* Spearow: Route 206
* Fearow: Route 206 (Rare)
* Natu: Route 206
* Xatu: Route 206 (Rare)
* Bidoof: Route 206
* Kricketot: Route 206
Route 207:
* Snorunt: Route 207
* Glalie: Route 207 (Rare)
* Spinda: Route 207
* Roselia: Route 207
Route 208:
* Bellsprout: Route 208
* Weepinbell: Route 208
* Victreebel: Route 208 (Rare)
* Shroomish: Route 208
* Breloom: Route 208 (Evolves from Shroomish)
Route 209:
* Psyduck: Route 209
* Golduck: Route 209 (Rare)
* Growlithe: Route 209 (Rare)
* Arcanine: Route 209 (Very Rare)
* Gligar: Route 209 (Rare)
Route 210:
* Lileep: Route 210 (Fossil)
* Anorith: Route 210 (Fossil)
* Gible: Route 210 (Rare)
* Gabite: Route 210 (Very Rare)
Route 211:
* Kricketot: Route 211
* Kricketune: Route 211 (Rare)
* Snover: Route 211
* Abomasnow: Route 211 (Rare)
Route 212:
* Bidoof: Route 212
* Bibarel: Route 212 (Rare)
* Starly: Route 212
* Staravia: Route 212
* Pachirisu: Route 212
Route 213:
* Machop: Route 213
* Machoke: Route 213 (Rare)
* Geodude: Route 213
* Graveler: Route 213 (Rare)
* Golem: Route 213 (Very Rare)
Route 214:
* Squirtle: Route 214 (Event)
* Wartortle: Route 214 (Event)
* Blastoise: Route 214 (Event)
* Pidgey: Route 214
* Pidgeotto: Route 214 (Rare)
* Farfetch'd: Route 214 (Rare)
Route 215:
* Zubat: Route 215
* Golbat: Route 215 (Rare)
* Hoothoot: Route 215
* Noctowl: Route 215 (Rare)
Route 216:
* Caterpie: Route 216
* Metapod: Route 216
* Butterfree: Route 216 (Evolves from Metapod)
* Weedle: Route 216
* Kakuna: Route 216
* Beedrill: Route 216 (Evolves from Kakuna)
Route 217:
* Pidgey: Route 217
* Pidgeotto: Route 217 (Rare)
* Spearow: Route 217
* Fearow: Route 217 (Rare)
* Farfetch'd: Route 217 (Rare)
Route 218:
* Snorunt: Route 218
* Glalie: Route 218 (Rare)
* Spinda: Route 218
* Roselia: Route 218
Route 219:
* Squirtle: Route 219 (Event)
* Wartortle: Route 219 (Event)
* Blastoise: Route 219 (Event)
* Starly: Route 219
* Staravia: Route 219
Route 220:
* Ralts: Route 220
* Kirlia: Route 220 (Rare)
* Gardevoir: Route 220 (Very Rare)
* Gallade: Route 220 (Very Rare)
* Bidoof: Route 220
* Bibarel: Route 220 (Rare)
Route 221:
* Pidgey: Route 221
* Pidgeotto: Route 221 (Rare)
* Spearow: Route 221
* Fearow: Route 221 (Rare)
* Shroomish: Route 221
Route 222:
* Bidoof: Route 222
* Bibarel: Route 222 (Rare)
* Starly: Route 222
* Staravia: Route 222
* Pachirisu: Route 222
Route 223:
* Zubat: Route 223
* Golbat: Route 223 (Rare)
* Hoothoot: Route 223
* Noctowl: Route 223 (Rare)
Route 224:
* Zubat: Route 224
* Golbat: Route 224 (Rare)
* Hoothoot: Route 224
* Noctowl: Route 224 (Rare)
Valley Windworks:
* Wingull: Valley Windworks
* Pelipper: Valley Windworks (Rare)
Lake Acuity:
* Shellos (East Sea Form): Lake Acuity
* Gible: Lake Acuity (Rare)
* Gabite: Lake Acuity (Very Rare)
* Garchomp: Lake Acuity (Extremely Rare)
Lake Verity:
* Shellos (East Sea Form): Lake Verity
* Gible: Lake Verity (Rare)
* Gabite: Lake Verity (Very Rare)
* Garchomp: Lake Verity (Extremely Rare)
Lake Valor:
* Shellos (East Sea Form): Lake Valor
* Gible: Lake Valor (Rare)
* Gabite: Lake Valor (Very Rare)
* Garchomp: Lake Valor (Extremely Rare)
Snowpoint Temple:
* Snorunt: Snowpoint Temple
* Glalie: Snowpoint Temple (Rare)
* Spinda: Snowpoint Temple
* Roselia: Snowpoint Temple
Mt. Coronet:
* Zubat: Mt. Coronet
* Golbat: Mt. Coronet (Rare)
* Hoothoot: Mt. Coronet
* Noctowl: Mt. Coronet (Rare)
* Snorunt: Mt. Coronet
* Glalie: Mt. Coronet (Rare)
* Spinda: Mt. Coronet
* Roselia: Mt. Coronet
* Gible: Mt. Coronet (Rare)
* Gabite: Mt. Coronet (Very Rare)
* Garchomp: Mt. Coronet (Extremely Rare)
Iron Island:
* Machop: Iron Island
* Machoke: Iron Island (Rare)
* Geodude: Iron Island
* Graveler: Iron Island (Rare)
* Golem: Iron Island (Very Rare)
* Beldum: Iron Island (Rare)
* Metang: Iron Island (Very Rare)
Celestic Town:
* Bidoof: Celestic Town
* Bibarel: Celestic Town (Rare)
* Starly: Celestic Town
* Staravia: Celestic Town
* Pachirisu: Celestic Town
Pastoria City:
* Wingull: Pastoria City
* Pelipper: Pastoria City (Rare)
* Staryu: Pastoria City
* Starmie: Pastoria City (Rare)
Veilstone City:
* Ralts: Veilstone City
* Kirlia: Veilstone City (Rare)
* Gardevoir: Veilstone City (Very Rare)
* Gallade: Veilstone City (Very Rare)
* Bidoof: Veilstone City
* Bibarel: Veilstone City (Rare)
Hearthome City:
* Pidgey: Hearthome City
* Pidgeotto: Hearthome City (Rare)
* Starly: Hearthome City
* Staravia: Hearthome City
* Pachirisu: Hearthome City
Jubilife City:
* Bidoof: Jubilife City
* Bibarel: Jubilife City (Rare)
* Starly: Jubilife City
* Staravia: Jubilife City
* Pachirisu: Jubilife City
Sunyshore City:
* Machop: Sunyshore City
* Machoke: Sunyshore City (Rare)
* Geodude: Sunyshore City
* Graveler: Sunyshore City (Rare)
* Golem: Sunyshore City (Very Rare)
* Pidgey: Sunyshore City
* Pidgeotto: Sunyshore City (Rare)
* Starly: Sunyshore City
* Staravia: Sunyshore City
Canalave City:
* Zubat: Canalave City
* Golbat: Canalave City (Rare)
* Wingull: Canalave City
* Pelipper: Canalave City (Rare)
Floccesy Ranch:
* Bidoof: Floccesy Ranch
* Bibarel: Floccesy Ranch (Rare)
* Starly: Floccesy Ranch
* Staravia: Floccesy Ranch
Fullmoon Island:
* Ralts: Fullmoon Island
* Kirlia: Fullmoon Island (Rare)
* Gardevoir: Fullmoon Island (Very Rare)
* Gallade: Fullmoon Island (Very Rare)
* Bidoof: Fullmoon Island
* Bibarel: Fullmoon Island (Rare)
* Starly: Fullmoon Island
* Staravia: Fullmoon Island
* Pachirisu: Fullmoon Island
Newmoon Island:
* Bidoof: Newmoon Island
* Bibarel: Newmoon Island (Rare)
* Starly: Newmoon Island
* Staravia: Newmoon Island
Dawn/Dusk:
* Duskull: Dawn/Dusk
* Dusclops: Dawn/Dusk (Evolves from Duskull)
* Misdreavus: Dawn/Dusk
* Drifloon: Dawn/Dusk
* Drifblim: Dawn/Dusk (Evolves from Drifloon)
Events:
* Squirtle: Event
* Wartortle: Event
* Blastoise: Event
Trades:
* Manaphy: Trade
* Phione: Trade
Note: The rarity of Pokemon is subject to change depending on the version of the game and the player's progress. It's recommended to use a Pokemon guide or online resources to find the most up-to-date information on specific Pokemon locations and their rarity.
This list provides a comprehensive overview of where to find all Pokemon in Diamond. Happy hunting!