Look for "Squat Rx" on Youtube. Search for "squat technique" on Youtube. Google "Starting Strength Wiki".
Are you practicing bodyweight squats to nail down the form? How close together are your feet? Are your knees in line with your toes when you squat? Which direction are your toes pointing? Where are you looking? Do you stretch beforehand?
For protein, check out the D&S forum. Folks here tend to say eat protein with every meal, and try to get a good amount within an hour or so post-workout.
I would focus on regular back squats before you move onto other variations if you are having trouble with balance.
