If you like tourneys and sit and gos, then I would recommend The Full Tilt Poker Strategy Guide Tournament Edition. It has sections by Andy Bloch, David Grey, Chris Ferguson, Mike Matusow, Ted Forrest, Gavin Smith, and others. It focuses mainly on Hold 'em, but Matusow writes a section on Omaha Eight or Better, Ferguson writes a PLO section, and a few Stud Sections. If you haven't read Doyle Brunson's Super System, you should read it as well as I believe it is a nice building block for future reads, although it focuses almost entirely on cash games.