Hello and welcome, misfortune partner
I'm as newbie as you (at least), so my advices and recommendations will be mostly unuseful...
In my opinion, the best way is trying to get a global picture of how these systems works (what is a loop, how calls are treated, what is that DN thing that everybody talks about...), and then a global picture of how your particular system works (dial plans, ranges, IPs...).
And then... wait. Let the task, problems and headaches to arise and then investigate on NTPs, ask in this forum (thank everybody again), and try to find someone near you that could be a guru (and be his/her shadow
).
Nothing more, nothing less... Welcome to the jungle; we will meet around here
P.S.- jocking apart, if anyone has a reference book instead Nortel Documentation, something like "Superloops for dummies", it'll be a really invaluable help.