Another person in the forum has found the step process to work for the $50 robot;From the main index of the $50 robot (http://www.societyofrobots.com/step_by_step_robot.shtml), I simply followed the instructions under "Step 4 - Programming" for the initial robot, then added code from "Bonus! UART Tutorial Step-by-Step" and "Bonus! Rangefinder Upgrade" Beware of the implications of changing the clock speed in terms of delay and servo commands!
Other than that, I am working on learning AVR Studio 6, which seems to bypass a lot of items before,
and simplify programming immensely. AVR 6 has a powerful feature, such as MCU simulator for most Atmel
processors. You can "simulate" inputs and outputs to create your program for your MCU without touching
it at that time. Check out my post, Analyzing the Axon: Coding, Construction, and Contraptions,
in the Misc section. That gives information I acquired along the path to where I am now.