Hey dude, this is probabaly one of the most common things new guys ask when they come on here. First of all, address the factors that influence your training at present and alter them to try and produce more growth and strength gains (adequate, plentiful and correct nutrition within your diet, enough rest, varied training program thats constantly difficult for your body to adapt to etc). You'll be surprised how just changing small things in these areas lead to extra progress you swore you'd never see again. As for getting bigger yet becoming leaner, its achieveable, yet you won't make progress in size as you'd wish. Basically, you either have to bulk up (eat more calories than your body uses up) or diet down (eat less calories than your body uses up) to really get anywhere, so make you mind up what you want to do first. If its leaner you want, don't expect your body to grow vast muscle mass if you're withdrawing calories (energy) in order to lose fat and become lean. The body simply doesn't work that efficiently and effectively. As for some of the basics out of the way, look at steroids and learn about them and their effects, their side-effects, their reactions to other steroids etc, long term and short term effects, how you administer them, how long you take them, what you take when coming off steroids etc. There is untolds to learn, and it is all important if you want serious results and care about your health.
As a rule, to consider taking steroids, you have to be comfortable with the concept of injecting them as that is the most effective and arguably the safest way to take them. If you're not ready for that, then you're not ready for steroids. Tablets such as Dianobol/Winstrol aren't advisable to be taken alone as they are toxic and taxing on the liver and your bodies lipid (fat) systems, especially if on them for eight or more weeks as you mentioned. They are good steroids to stack with injectibles, but pretty useless by themselves.