For official release packages, please see the stellarium.org main page.
Older versions can be downloaded from the project download page.
Please do not report bugs found in unofficial builds. Also, treat them as you would any software whose source cannot be easily verified (i.e. with caution).
Many Linux distributions provide fairly recent binary packages, so you do not have to build from source if you use one of them.
If you have, or know about, other unofficial builds (previews etc.), you can list them here.