Pokemon Go is a very popular game in Australia. To find new Pokémon you need to walk through the streets of Australian cities.
Find rare Pokémon is not as easy. Especially Pikachu.
If you want to see the location where there is a Pokémon, you can use the maps that make Pokémon trainers themselves.
Pokecrew - Crowdsourced Pokemon Go map
PokeMapper - Share and find #PokemonGO creatures
As a bonus list of rare Pokémon.
Everywhere:
Rattata, Pidgey, Weedle, Venonat, Zubat, Caterpie, Doduo,
Common:
Oddish, Paras, Gastly, Drowzee, Eevee, Magikarp, Meowth, Bellsprout, Ekans, Nidoran M/F, Polywag, Slowpoke, Goldeen, Krabby, Mankey,
Uncommon:
Spearow, Growlith, Jigglypuff, Cleafairy, Psyduck, Seel, Abra, Geodude, Sandshrew, Vulpix, Diglett, Exeggcute, Tentacool, Shellder, Onix,
Rare:
Machamp, Ponyta, Weezing, Voltrob, Horsea, Staryu, Tangela, Cubone, Ryhorn, Grimmer, Magnemite, Scyther, Lickitung,
Special:
Bulbasaur, Charmander, Squirtle, Pikachu, Omanyte, Kabuto, Aerodactyl, Hitmochan, Hitmonlee,
Epic:
Dratini, Farfetch'd, Mr.Mine, Jynx, Magmar, Electabuzz, Porygon,
Myths:
Lapras, Snorlax, Kangaskhan, Chansey