It's fairly hardcore, but there are "worse" out there. Falcon 4 is definitely harder to learn. I can't speak for Black Shark or the SH series.
You don't need the
printed manual--and I don't think it's available anymore--but RTFM is non-optional for this one. Not necessarily the whole thing at once, but definitely the sections applicable to every platform and to the platform you want to learn first.
Tutorials... there are a few, but it seems that with each sim in the series, the tutorials got a bit worse. The community has tried to make up for it; see, e.g.:
http://www.subguru.com/DW_missions/ASW_training.zip
http://www.subguru.com/DW_missions/FFG_TA_Training.zip
P-3 training:
1 2 3
http://www.subguru.com/DW_missions/S...g_missions.zip