how to deliver an application

[jimgardener]

hi
i have written a program that takes in user input thru a gui and then
does some calculations and then displays a result value.I have split
the code into 3 parts

1.the gui code--mygui.py  containing a class to handle all ui stuff
2.calculations.py (also has one class to do all processing)
3. documenthandler.py contains a class to deal with a specific type of
document(say .doc , may be later i will add other document support
here)

i run my code by calling python mygui.py
and this will call class from calculations.py to do the processing.
calculations.py will in turn call the class and fns of
documenthandler.py when needed

currently i have put all three .py files in one folder and run the
application.I would like to know if this can be packaged  better?
Finally how should i deliver the application? i would like to have
both windows and unix users be able to use my app

any advise most appreciated
jim