Adding bulk to your body depends on your body type. Some people just don't have the frame to add much bulk and it takes more work. Some are blessed with the type of frame that can add bulk without problem. Are you tall/skinny, short/husky, or proportioned evenly? The latter is the best for adding bulk easily. I tend to fall in that category and when I lifted heavy, ate properly and included cardiovascular training I added weight and lost inches in my waist. I found reading Muscle and Fitness magazine a great resource for proper training and diet. Granted some of the models in the magazine use other "enhancers" to get that ripped, but you can get good results without going to those extremes.