i need to make my website and need to import 60.000 users

Hi, i need to make my website and need to import 60.000 users from my old magento database.
I kinda don't know nothing about this multsite thing.... but i like wordpress.
There's any way to turn this Batch Create in something like Batch Creat WP? Or maybe add this function of import at add new users plugin... i don't know what could be easier.
But when i tried here that "add new users", it would take soooo long, that i got bored just thinking.