1. Modern tar (or at least the version in RHEL) detects compression. Hence
tar tvf lplinux.tar.bz2
tar xf lplinux.tar.bz2
should work.
2. If head shows only 4 lines, then the tarball has only 4 files, for head shows (up to) 10 lines by default.
3. Those four lines show no "lplinux". If the tarball has no directories in it, then extracting from it will not create any directories.
4. I have a habit of first looking at the tarball contents with 'tar tvf' before I decide where I want to extract from it. In case of "no directories" tarball I would first create a directory and then extract there.
5. Where did you get your mantra:
tar xjvf lplinux.tar.bz2 && cd lplinux && ./install_lastpass.sh