I am a wrestler and for next season i need to gain around 6 or 7 pounds of muscle to bump up a weight class i wont to know the best supplements for gaining weight and good supplements for turning it into lean muscle
If you want to gain weight, increase your calorie intake. The "supplement" you're looking for is called food.
Also, you can't "turn" one kind of weight into another. Your base body weight (excluding the contents of bladder and digestive tract) consists of lots of components, but we're only worried about three:
1) Fat stored in adipose cells.
2) Water stored in muscle tissue.
3) Protein stored in muscle tissue.
1: The amount of fat stored by your body changes with the difference between calories in and calories out, so to change how much fat your body carries, either change calories in (what you eat) or change calories out (your metabolism - stimulants, exercise, dietary constituents and patterns).
2: The amount of water stored in your muscle tissue (when fully hydrated) is generally determined by the amount of certain chemicals in it. One of these chemicals is phosphocreatine. If you supplement with creatine, your muscles absorb more of it, and consequently absorb more water to keep the concentration stable. There are plenty of weight-training routines designed to encourage what is called sarcoplasmic hypertrophy (often just called hypertrophy for short).
3: The amount of protein built into your muscle tissue doesn't affect your body's mass as dramatically as the other two factors (muscle tissue is mostly water), but it can be built by workouts designed to induce myofibrillar hypertrophy in combination with a diet with adequate nutrients (particularly protein and calories).