Are you doing all of that in each workout? If you are I'd say your not pushing yourself hard enough. If you were there's no way you could manage that in one session.
First off, if your doing a full body session then thats fine, but Id suggest maybe cutting down the exercises themselves and focussing on maybe two for each area (so 2 biceps, 2 triceps, 2 chest etc). The number of reps could possibly be looked at as well if your training for size. Rather than 3 sets of 10, try going for 5 sets of 5, or 6 sets of 4. If you do that, work with the idea of upping the weight each session - if you can manage 5 reps easily then its too light, up the weight. Similarly, if you can't manage 5 then its too heavy, so reduce the weight. Holding your form is vital, it's no use pushing 5 out at a weight that you can't handle without losing your form.
The other thing that you don't mention though, is your diet. That's just as important (if not more so) than your routine. What's that like? How much do you eat? How often? If your not gaining and your routine is decent it will more than likely be because your not eating enough to do so. Loads of protein. Loads of (complex) carbs. Good fats (fish, nuts). Fruit. Veg. Overall, a good balanced diet.
Oh, and don't worry about other people at the gym. They may be 'assisted', or they may just have been training for a lot longer than you. It takes a long time to gain lean mass. Patience is probably the fourth key ingredient (behind routine, diet and rest).
