All the contents are stored in the alf_data folder. This folder is relative by default so it depends on where you choose to launch Alfresco. This relative path thing is not recommended (you'll create different alf_data folders if you run the startup script from another path the next time) so you should change this path to something more definitive in the repository.properties file.
Changing the dir.root property, which defaults to ./alf_data, to point to a permanent location is considered the next step after the initial "What's this Alfresco thing?" cursory install. Ideally, the properties will have been set before the first system startup … but then no-one would bother. :wink:
