Currently three fourths of bookstores use a computerized POS system to some extent in their store operations, but may not necessarily use automated ordering processes built into those systems. Stores may also manually build purchase orders in POS systems that can be transmitted to those select few. Typically these systems are very efficient for placing such orders.
Many stores still call in orders.
You can enter your orders in short spurts in between customers, after closing when the vendor telemarketing departments are closed, or enter special requests for individual customers while they are there, and then batch input into daily, weekly or semi-weekly vendor orders. In the batch input, you just enter ISBN and quantity for each item. A 25-book order takes less than one minute to enter. You can also search a specific title and click to enter it. In those cases, you can always link to the Publisher Directory Listing page and contact them directly to place an order.