Go to fallarbour town nd head to ur extreme left..then go down south..then u will find stairs..then just climb the stairs all the way.And u will find a cave..enter the cave,this is meteor falls!
there is no diglett cave in Pokemon ruby only in leaf green and fire red
You can go back to the Professor in the town and give him the Meteorite. He'll give you a TM in exchange.
North of Rustboro City near route 114 and route 115.
in the granite cave
fire cave
sootopolis
in sootopolis
Once you get the meteorite from Team Magma, take it to Prof. Cosmo in Fallarbor Town, he'll give you a TM for returning his meteorite
Bagon can be found in the smallest room of Meteor Cave (the cave with the meteorite and the scientist).
it's found in a remote location hidden in meteorite falls.
I don't think you can get regirock in pokemon ruby.
the island cave is on route 105.