Is there a PPA of Panda3D 1.8.x for Ubuntu 12.04 64bit

There is none, but you can add the repo from oneiric and it should work (does here).

Just add this line to /etc/apt/sources.list:

deb archive.panda3d.org/ubuntu oneiric main

Also there are snapshots for precise here: panda3d.org/download.php?pl … =devel&sdk