My 2 cents,
Look at Joe Defranco's Westside for skinny bastards routine, as far as supplements go, a good Protein powder (a weightgainer type), other than I'm not really big on supplements. After you train for about 6-8 months maybe get some creatine. As far as diet goes, 50% carbs 30% Protein and 20% fat. Don't force feed yourself, or you will get sick of eating. Eat foods that are caloricly dense such as peanut butter, guacamole, steak, pizza, spagetti, ice cream, or lasagna.
Don't worry about what everybody is doing or gaining, there is always someone bigger than you, but the guys that are bigger than you also wish they could eat like you and be ripped. Concentrate on being the best you can be. You will be able to be more ripped than guys bigger than you. Train hard and look at your gains every 6 months then reevaluate your training and diet.