/users/applications is not likely to be your Applications folder. The main Mac Application folder is /Applications. Home folders are stored in /Users (so one would expect /Users/applications to be the home folder for the user with short username applications). You might have a folder called Applications in your home folder (i.e. /Users/[yourusername]/Applications, or ~/Applications for short) - CrossOver puts stuff there, for instance. Finally, Unix-style command line programs are stored in a variety of places (some of which are hidden in the Finder) such as /usr/local/bin or ~/bin, more or less corresponding to the Unix directory structure.
As an alternative, if you have access in the Finder to the folder containing the file you want, you can add it to a command line by simply dragging it onto the Terminal window. For instance, to cat a file you would type cat (note the trailing space), then drag the file onto the Terminal window from the Finder. It will be replaced with its full path, and you can then run the command.
Bear in mind that you don't need to be in the same directory as a file to reference it - just provide a full path (i.e one that begins with /) or use ../ to refer to a relative parent directory (but beyond one or two levels the latter quickly gets confusing).
