Accessing object constructors from the 'main'

The Moose::Manual is very well written, but is definitely lacking in
explanation of a very key step in product development: how on Earth do you
actually use your objects in a script?!

Specifically, my problem is that I want to have a *main.pl* from which I
call *Obj->new( ... );*
What I can't figure out is how I'm supposed to do this from a different
file than the original *Obj* definition. Currently, I'm making it work by

> *use Moose;
> extends 'Obj';*

but this seems like it can't be the Best Practices way to go about is... Is
there a more "proper" way to access an objects constructor from a different
document?

Thanks,
Faelin