[Koha] Where do you get you cataloguing info from?

Gidday All I'm the Computer Technician/Systems Admin at our new school and we are looking for a library system here at Great Southern Grammar (Albany Western Australia). Our librarian is concerned about the cataloguing and search facilities of koha. I've looked at the stuff on MARC and as far as I can see, it does provide what we need, but then I'm not a librarian. Are you using some version of MARC or do you get your cataloguing info from somewhere else? Are there any "free" versions/subscriptions available? (Being a new school we don't have a lot of money to play with yet.) Thanks for any help Max Stam