SQLite is a single-file database which follows the zero-configuration approach. It is furthermore easy to use and is thus perfect for your first experiments with liquibase.
There is a jdbc driver available here: https://bitbucket.org/xerial/sqlite-jdbc/downloads/
To use sqlite with liquibase you will need the following information:
jars for the classpath:
jdbc driver name:
jdbc url:
There is no need to create a database before you can use sqlite, as I said: it follows the zero-configuration approach.
A run of liquibase with sqlite, having the sqlite.jar and the in the current directory (and the liquibase.jar at hand as well), could look like this: