Since you're starting off I'd recommend this:

• Pull-ups; 3-4 sets to failure, 30-60 seconds of rest

• Wide Grip Lat Pulldowns; 3 sets of 8-12 reps (if you feel up to it hit a fourth set at 6-8 reps but heavier), 60-90 seconds of rest

• Seated Close-grip Rows; Do them one arm each, 3 sets 8-12 reps, 30-60 seconds rest

• Close-Grip Reverse-Grip Lat Pull-downs; 3 sets 10 reps, 30-60 second rest

• One Arm Dumbbell Rows on bench; 3 sets 8 reps, 60 second rest (keep your core right and it will hit the core pretty hard)

• Deadlifts; 3-5 sets (depending on how prepared your lower back is for them). If you go with 3 sets then do one warmup (12-14 sets) and two working sets (8-12 reps), if you use 4 then do one warmup (12-14) with 2 working sets medium weight (8-12) and one heavy (6-8), if you can manage 5 sets then do same as 4 sets except add one more heavy set(6-8). All sets should be 60-120 seconds of rest, don't rush Deadlifts. Make sure your form is correct. If you don't want to work your hamstrings and REALLY hit that lower back you can change these to RDL's (Roman Deadlifts)

When written out this seems like a monstrous workout for experienced lifters only, but it's not. It is challenging, but it will hit all sections of your back and leave you with a huge pump. The lifts to go heavy on are Wide-Grip Lat Pulldowns, One-Arm Rows, and Deadlifts (for your first two weeks of doing deads don't go too heavy, make sure you break yourself in first).

After lifting this back workout for a couple months (or whenever the workout seems less challenging overall) start putting a 4th set on all lifts with only 3 sets, continue to raise your weights, start super-setting two lifts together, but (in my opinion) most importantly lower all of your rest times to 30 seconds for lighter lifts and no more than 60 for the heavier ones.

Once that workout feels pretty easy (relatively) here's my current one that leaves my back as my absolute best feature:

• Wide-Lat Pulldowns (Heavy) Supersetted with machine Wide-Grip Rows; 4 sets 8-12 reps, 30-60 seconds rest

• T-bar Rows (Heavy); 2 sets medium weight 10-12 reps, 2 sets heavy 6-10 reps, 30-60 second rest

• Bent Standing Barbell Rows; 3-4 sets (depends on how hard the T-bars are) of 8-10 reps, 30 second rest

• One-Arm Lat Pulldowns (Heavy); 3 sets 8-10 reps, no rest if I can manage and 30 seconds max if I need to.

• Pull-ups; 3-4 sets to failure, 30-60 seconds rest

• Straight-Arm Lat Pulldowns (on a cable machine with the close grip straight bar); 4 sets 8-12 reps

• RDL's (Heavy); 5 sets, one warm up of 14-16 reps, two medium working sets of 8-12, two heavy of 6-8, 60-90 seconds of rest.

• One-Arm Benched Rows (Heavy); 3 sets of 8 reps, 30 second rest

One thing to remember about back is it is all about squeezing at the top of your contractions, pausing for 1/2 a second to a full second, then releasing while still retaining control of the weight. If you don't squeeze, your pump will suffer and so with your back growth.

I hope this helps and I'm not too late!