One more thing, size does not equal strength. I am 140, 22, and get the you're a lot stronger then you look compliments a lot, both in the gym, and when grappling. Most of it's mental, I believe I am stronger and so I am. Don't discredit that. The other of course is I work towards strength more than size. I like being lean (not even wrestler-cut, just an above-average fit 140lb, 5'8 dude), I like having cardio that goes for days, I like my opponents underestimating me when I enter divisions where the limit is 10lbs over my weight, and they have all cut from 150-160. It gives you a mental edge when they lock in and realize you are no push-over. I'm telling you, just believing you are stronger is 50% of the game, the other 50% of the game is what you do with the bar in the gym.
For both size and strength look into the compound lifts, 5x5's for strength, 5x8-12's for size. Isolation work where you need it. I usually do a compound lift, a major exercise for the other half of my body, a horizontal row of some sort (t-bar rows all day), pull-ups (add weight too!), any isolation work, and an exercise to work the antagonist muscles around the isolation work.
Seriously, row. Rowing builds size and strength. I LOVE rowing probably as much as I love Squats, and I love squats like I love women. Vertical rowing motions (pull-ups) build width; horizontal rowing builds thickness. Don't neglect!