GPL and software I have written

["Brooks R. Robinson" <brooks.robinson@rides.com>]

Greetings!
	I have a dilemma, and I expect this to end in a flame war, but here goes...
I am a computer science student, and I also work as a system administrator.
For one of my classes, I have written an e-commerce package.  It is written
in C using GCC, it uses Mini-SQL, and runs on Apache as a CGI program.  My
employer has expressed interest it this particular piece of software (my
e-commerce package).
	I have issues with my employer that cause me to not want to merely hand
over my work.  I have never released/published any software that I have
written, so I am treading into new territory.  Therefore, I have read
through the GPL, and I think I understand, but I would like confirmation.
Since I am not modifying any existing software, I am creating new software,
I can charge for the new software.  This could be a license fee or
something.
	I, of course, cannot and would not charge them for GCC, Apache, or for that
matter Linux in general, except to the extent that I provide them a
distribution (I burn a CD for them and/or install it on a computer).
Mini-SQL has it's own license (NON GPL) that they would have to purchase
separately (I developed this as a student, so I am not require to pay money
for a license, but they would as a commercial site/use).
	In essence, I am providing them C code, which they can compile and execute.
Am I in the ballpark or have I gone off the deep end?

Thanks,

Brooks