30 pounds in two years is very impressive. Great gains guitarman. It takes the bodybuilders you see on stage and in the mags YEARS (10, 12, even 15) to get where they are. Keep plugging away and you stand a shot at making it.
For lifting, Jaster posted this advice and it is great! Lift hard - lift heavy - lift big - lift often. Great advice. Stick with the compound exercises as they add the most muscle.
Don't forget to eat a LOT of food! That is key to
gaining weight. Keep to lean meats, veggies, complex carbs. Stay away from fast foods and
processed foods as much as possible. It will put the wrong kind of weight on.
Rest as much as possible. Your body needs to recover from the workouts. Get plenty of sleep. Nap if you can.
Stay focused. If your goal truly is to go on stage then keep that goal foremost in your life. You will still need your studies and relations with other people. Learn balance in all of your life - and you can still remain focused on getting much bigger.
You should do well.