shouldnt ask on this forum
too many ppl that dont know anything n u will be mislead
listen to hypertrophy n speedy, they know what their talking about
basically, what you want to do is widen your back, this is what makes the v shape.
do wide grip pull ups (if you can) for heavy (8-10 reps) 4 sets. (of course after a warm up). then do 4 sets of another 8-10 reps with close grip.
i can't remember, but i think wide grip works the upper lats, while close grip works the lower part of the lats.
also, to thicken your back, bent over dumbell raises (i think that's what they are called). but i think maybe ur dumbells r too light.
you also want to widen ur shoulders by doing dumbell side lateral raises which does the lateral deltoid head of your shoulders. no less than 10 reps for this, perfect form (no cheating) is essential coz otherwise culd stuff up ur shoulders.
nutrition is very important also. no matter how much u try u could never gain n e muscle unless you eat heaps (and healthy). General rule of thumb - if your not full, you should be eating.
just remember that this number of reps and sets is for mass building. dont just go start doing this straight away, work up to those reps/sets by starting off with around 15 reps and fewer sets. oh, and if you aren't failing (that is, struggling for another rep without cheating) or close to it on ur last reps, then you are wasting ur time.
i personally followed this n got awesome results in a short period of time.
http://exrx.net/Exercise.html
go to exercise body map