Service Catalog belongs to monitoring plugin.
I would recommend using appliances for your purpose.
Service catalog is currently available using the formcreator plugin
but with formcreator they create forms, not a ticket directly.
I think that screen is awesome, but they add another layer (forms) that in various cases is unnecessary.
Infotel has a plugin for service catalog that is awesome too. http://blogglpi.infotel.com/nouveau-developpement-infotel-la-creation-de-ticket-facon-catalogue-de-service/
Thanks for your suggestion.
Official GLPI Formcreator Plugin does this feature (service catalog UI, custom forms, multiple ticket destination, etc...) : http://plugins.glpi-project.org/#/plugin/formcreator
GLPI core integration is planned.
Customer support service by UserEcho