TSN is reporting the NHL is anticipating a 48 game season:

http://www.tsn.ca/nhl/story/?id=412970

In any event I agree with Pengwin that it will be a 14-15 week regular season. In a 12 team league 14 weeks works perfectly:
1 x 11 teams = 11 weeks + 3 week playoffs = 14 weeks. For 15 weeks you'd play one team twice.

I don't know about yahoo but espn allows you to custom enter a schedule if you want. My 12 team league has divisions and so we've re-written the schedule to where you play every team once and the last 3 weeks of the season are in-division games to add drama at the end of the year.

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12 team H-2-H 1 year league, daily roster 3 goalie start minimum
2xC, 2xRW, 2xLW, 4xD, 3xUtil, 2xG, 5 Bench
G, A, P, +/-, PIM, PPP, SHP, GWG, Hits, W, SV%, GAA
C: Stamkos,Thornton, Riberio, Stepan, Desharnais, Clune
LW: Moulson, Dupuis, Prust,
RW: Kessel, P. Kane, Wheeler, Stempniak
D: Hamonic, Zidlicky, Franson, Muzzin
G: Bryzgalov, Hiller, Fasth