Billy bookcase in IKEA ballymun

there will be an article number on the item you need. They have computers there to put it in and it'll tell you where it is, alternatively there's a customer service desk and just give them the article number and they'll tell you

Order it for collection. They'll bring it to you.

Fastest way to get things.

Doubtful when it's busy. You book a time slot.

All the locations are available on their website