Set your PATH environment variable.
I assume from your username that you are on Windows of some sort.
Go to Control Panel -> System -> Advanced - >Environment Variables
Somewhere in there will be PATH. Add the directory that holds you javac to this path (be sure to use ; to seperate elements of your path)
> ... Or you can type in the path of the program:
>
> "/Program Files/Java/jdk1.6.0/bin/javac" Foo.java
>
> The quotes are needed because of the space in the
> folder "Program Files"
Or, if you're already going to go through the convoluted mess of typing out the full path every time you want to run the executable, you could further muck things up by typing:
/progra~1/java/jdk1.6.0/bin/javac [filename]
(Hint: just fix your path variable. ;-)