A lot of it comes down to experience.
In just your 2nd year the best outcome for you is probably just to absorb as much information as you possibly can.
Get familiar with player's names and team superstars and continue to learn the ropes of fantasy hockey. What are the fantasy indicators of success to look for, and keep following sites and forums to get the latest up to date info.
I've written a few articles the past few weeks that highlight the potential top-six of each team. Generally most are pretty set, with a few other key names to keep an eye on. Take a gander at those if you haven't done so yet.
West Articles
http://www.dobberhockey.com/index.ph...n-ma&Itemid=77
East Articles
http://www.dobberhockey.com/index.ph...ller&Itemid=99
Just keep scrolling through for each article. There's 5 for each Conference, with the last one coming out on Thursday this week for the East.
One tidbit about line combinations is that they change all the time. It changes from game-to-game and possibly even period-by-period. So don't rely too much on thinking that the same three players will line up with each other for the duration of the season.
If you want to look up the top-6 for each team the easy (albiet not entirely 100% accurate) way of doing it is to go into NHL.com and go under stats, and sort it by the team that you want then sort the data by TOI/G.
Generally speaking the top-3 players that are on top of the list (who garner the most ice-time) are the top-line players, then the next 3 are probably the 2nd line players and that generally sorts out the top-six vs the rest for teams.
Another quick way is to go to the same section Dobber Fantasy Tools and go under Line Production, and select Team FWD and it should list the most productive lines from the entire year.
eg.) you should get Buffalo:
Connolly, Hecht and Pominville was the most productive at 48 points
Hope it helps