I am working on Mac OS X, I want to create a new SQLite DB, and I am using http://www.sqlite.org/quickstart.html as a reference.
I am entering: sqlite3 test.db
It worked. Quit out and test - the database has been created.
You are now in the SQLite shell, and it is ready to receive commands like CREATE TABLE..., INSERT INTO..., etc.
If you would prefer not to use the interactive shell, you can build your schema straight from the command line:
sqlite3 test.db "CREATE TABLE ..."
Or just create an empty database with no schema:
sqlite3 test.db ""
But that's the same as just creating an empty file, anyway:
touch test.db