Use this direct link to book a camping reservation at Alpine: https://campreservation.com/640/Camps/555
You can create an account if you plan to make multiple reservations, or you can book as a guest!
Scroll down and look at the facilities before booking, and then there is a button at the top right to make a reservation. The system will walk you through the reservation process.
Find a How-to Guide that can walk you through the process of booking here: https://alpinescoutcamp.org/wp-content/plugins/download-attachments/includes/download.php?id=1868