Congratulations!
Visit frequently with treats and toys (with bathroom door shut behind you).

Use a feather toy or string toy to lure baby out from hiding. Sooner or later, he won't be able to resist the temptation!

As he gets used to playing with you/toy, keep pulling the toy closer and closer to you. Talk soothing baby kitty talk. You know what I mean!

I used this method on a feral kitten this fall. Your baby is domestic, so it shouldn't take long.

When she accepts you, it's time for introductions. Although, I recommend isolation for a while, as you're right--it's quite scary to leave your home and be transported to a strange with strange cats.

Good luck to you and New Kitty. (Did a miss a naming thread somewhere? )