Just saw this:
For a wide and strong back I'd use:
1) Chin-ups- Despite what was posted above the chin up is when your palms face outward, but this is petty bickering as there are 8+ variations that fall into the chin-up family of exercises. When you can do 10+ on your own, add weight. These are much better than lat-pulldowns.
2) One armed rows or barbell rows- These are great for adding thickness. Switch between the two, but if your form is spotty on the barbell type, stick with the dumbbell type while you profect your form. It's quite easy to tear a bicep or strain your back if your form sloppy in that exercise.
3) For your traps and as a general back strengthener, I'd go with the high pull(look it up here:
Address:
http://www.uwlax.edu/strengthcenter/videos/video_index.htm , it's in the first row). Shrugs are ok, but most folks use way too little weight to get the most out of that exercise. The High pull is better for sporting applications too.
I'd strengthen the posterior chain on leg days, using the either the deadlift or power cleans. I'd also do a few sets of hyper-extensions(or good mornings) on leg day also. The Abs are pretty muscles, but if your lower back isn't strengthened along with them, you'll have problems in the long run.
One last thing, try to work in the 5-8 rep range most of the time. This is a nice rep range that bridges the gap betwween pure strength work and hypertrophy.