If you eat and train hard you'll put on weight but you gotta eat a lot. You should be eating about 3 to 3.5kcal a day and concentrating on the basic compound lifts. Do deadlifts, squats and bench press going as heavy as you can and you will bulk up. The reason people don't put on weight is they don't eat enough and do isolation excersises like bicep curls. Keep it simple: eat lots and compound lifts. Don't think about gear until you've been training years in my opinion.