See also the Maxima ports page
You can download files from the Sourceforge download page.
The file release manager at Sourceforge has files for all versions and all releases of Maxima.
You want maxima-x.y.z.exe, a self-contained installer program.
For Slackware users, an installation kit is provided as maxima-x.y.z-i486-n_slack12.1.tgz. This file can be installed using the installpkg command on most recent (version 12.0 and up) Slackware systems. The package includes binaries for four Lisps (CLISP, GCL, CMUCL, and SBCL) though you may find that ”out of the box”, only the CLISP binary will function, as CLISP is included with Slackware distributions. Before you can run the other binaries, it may be necessary to download and install the appropriate Lisp.
For an installation from RPM, you want at least two files: (1) maxima-x.y.z-n.i386.rpm, which contains scripts and documents, and (2) maxima-exec-<lisp version>-x.y.z-n.i386.rpm, which contains an executable Lisp image. You may also want (3) maxima-xmaxima-x.y.z-n.i386.rpm, the Xmaxima graphical user interface, but it is optional.
The maxima and maxima-exec RPMs depend on each other. Specify both in the rpm command:
rpm -ivh maxima-x.y.z-n.i386.rpm maxima-exec-<lisp version>-x.y.z-n.i386.rpm
For an installation from source code, you want maxima-x.y.z.tar.gz or maxima-x.y.z-n.src.rpm. But you knew that.
Here are some notes that might be helpful. README.lisps tells something about Lisp implementations, and README.rpms tells something about RPM's.
To rebuild from the source, you want maxima-x.y.z.tar.gz.
You can obtain the latest development code at the Sourceforge GIT page for Maxima.
The Maxima project now manages its source code with Git.