In Solaris, packages are directories of the files needed to build or run a program. This is the mechanism Sun Microsystems uses to distribute software. If you are installing from a CD-ROM, the files will typically be laid out just the way you need them. You will only need to mount the CD-ROM so you can get to them. If you are downloading packages, you will typically need to unpack them first, usually with the tar command. You may want to do this under the default directory /var/spool/pkg, but you can override this location with command options when installing the package.
Once you have the appropriate package on your system, you can use one of several closely related commands to manage it. To install a package, use the pkgadd command. Without any arguments, pkgadd will list the packages on your system and give you the opportunity to select the package of interest. Alternately, you can name the package you want to install. You can use the -d option to specify a different directory.
Other commands include the pkgrm command to remove a package, the pkginfo command to display information on which packages are already installed on your system, and pkgchk to check the integrity of the package.
For other software in package format, you might begin by looking at http://sunfreeware.com or searching the Web for Sun's university alliance software repositories.