Was recently introduced to this site, great stuff.
Probably late into the game, with many drafts already completed, but at least I have an idea of what to check out for next season.
I have used The Forecaster, McKeens, DobberHockey and PrimePucks in the past. Currently I use Dobber and PrimePucks. Dobber has a wealth of information for the NHL, and good to read up on some of his thoughts (i.e. he is the one who introduced me to the 4th year breakout phenom), but I really love the prospects guide. I used to collect cards and used the prospect guide as players I would want to target. Sometimes the wealth of data could be too much.
I like PrimePucks as a different perspective. Also, it is concise and straight to the point in terms of analysis. One page, one team. Easy to flip through (printed) and scroll through (PDF file). I can print it out and take it with me, and it is updated quite frequently during the preseason. The sleepers and darkhouse section, one can find a few gems. The tier system is an excellent concept, and great in not missing out on some underrated players.
The other good thing is that the person who runs it, is available for questions.