Email a Custom Address When a Site Is Created
Sends a short notice with the new site's name, address and creator to an address you choose, in addition to WordPress's own network admin email.
Snippet Library
Multisite snippets for WordPress
Snippets for WordPress Multisite networks: network-wide settings, new site defaults, super admin tools and cross-site tweaks. For network administrators who manage many sites from one install.
Stop New Site and Signup Emails to the Network Admin
Stops WordPress from emailing the network admin every time a site is created or someone activates a new site or account, useful on networks that create many sites automatically.