Microcontroller based bar code decoder

I need someone that has a prior knowledge of how to design a microcontroller based bar code decoder (Preferably using PIC16F877A or PIC18F452 or Arduino). I only need a working design with list of components and the Microcontroller program. You must have tested and simulated the whole design before passing it to me. I will implement your working design here myself once i have a workable circuit and program. Program can be written in MikroC, Mikrobasic or Assembly. Use of Atmel will also be considered. I dont want something too big, just propose a simple design to me that will interface a Microcontroller to a bar code decoder (Like a shopping list application). Thanks and will be waiting.