You can catch one on Routes 101, 102, and 103. It's a very common Pokemon, so you won't have trouble finding one.
You can't catch a sentret in Ruby version, but you can catch one in Emerald version.
You can't.You have to trade it from Pokemon Ruby Version
I am sorry to say this but, you cant catch any of the Pokemon in platinum in ruby unless it is a hoenn Pokemon.
No you cant you can only get it in ruby version.
You have to trade with another version of pokemon.
You can't: you can only get it in a trade from a person with either Pokemon sapphire version or emerald version.
Pokemon ruby's version IS Pokemon ruby.
Kyogre is not able to be caught in Ruby Version.
Use pokeballs.
You should try to catch the Water Pokemon in the water areas of the game.
You can't catch Zekrom in Ruby version.
you catch more Pokemon on ruby...about 7.