TADS can be found at the interactive-fiction archive GMD. The current version of TADS is 2.2. TADS is distributed as shareware; to register you must mail order it from the High Energy Software (see TADS docs). The shareware version, however, does not have any deficiencies in it, so you can use it to full potential before deciding whether or not to register.
The generic documents for the TADS system is contained in the file pc.tads2doc.zip which are applicable to all supported platforms (although primarily for DOS), except for the Mac, which is available in both MacBinary format and BinHex format.
The TADS system is currently available for the following platforms:
Version 2.1.0 for AmigaDOS beta version for CLI only; please test it.
Version 2.2.0.5
Version 2.2.0.5, Unix Patchlevel 1, DEC MIPS Patchlevel 1.
Version 2.1.2.2 on for DOS on 386+ machines (Runs in protected mode, so it's
faster and uses all the memory on the machine.) Requires the standard DOS
package as well.
Unix Patchlevel 1, GO32 Patchlevel 1.
ZIP file. Also available in a Unix
tar/compressed format.
Unix Patchlevel 1, IBM RT Patchlevel 1.
Version 2.2.0.5 executables for Linux.
Unix Patchlevel 1, i386+ Linux Patchlevel 1.
Version 2.2.0.4
Version 2.2.0.4
Version 2.2.0.5
Version 2.1.1
Version 2.2.0.4. See also PC Protected-Mode and DOS 386+ packages.
Protected mode executables for MS-DOS running on 286 and later machines. This version can use up to 16M of memory, not just 640K of conventional memory like the standard (real mode) TADS in the PC package. If you want to use this, you will also need to download the PC package.
This updates the above v2.2.0.4 package to version 2.2.0.5
Version 2.2.0.5. Unix Patchlevel 1, SGI Patchlevel 1.
Version 2.2.0.5. Includes dynamically linked and static binaries.
Unix Patchlevel 1, Sun 3 Patchlevel 1.
Version 2.2.0.5, includes dynamically linked and static binaries.
Unix Patchlevel 1, SunOS Patchlevel 1.
Version 2.1.0. Includes dynamically linked and static binaries.