The Helpdesk Issue Manager is available free of charge from the project homepage at sourceforge (http://helpmeict.sourceforge.net/). The project is released under the GNU Public License, and as such can be freely downloaded and modified under the terms of that license. Current distributions come in a single downloadable gzipped tar file.
The first thing you need to do is create a new directory in which to put the downloaded file. This could be anywhere you have access to, but bare in mind it will eventually hold your documentation and related files. The best bet would be to put it somewhere in your home directory. Secondly you need to unpack the distribution using the following command:
#> tar xvzf helpdesk_archive_file.tgz
You will now find yourself with the following in your chosen directory.
LICENSE - A copy of the GNU Public License terms.
INSTALL - An overview of the installation.
README - A quick pointer to where to start.
database.sql - The database definition script.
docs/ - This documentation.
web-tree.tar - An archive of the PHP scripts.
Read on to find out what to do with them.