Ee Doc Smith
E.E. 'Doc' Smith has written the LensmanSeries, the SkylarkSeries, the FamilydAlembertSeries and some other novels. I've only read the LensmanSeries so far, which I can very much recommend if you like SpaceOpera's. -- LorenzBeyeler
Edward Elmer Smith, PhD Bibliography (his books' names, not his original magazine series' names)
The SkylarkSeries
TheSkylarkOfSpace (the magazine serial had Mrs Lee Hawkins Garby helping with the love interest portions), SkylarkThree, SkylarkOfValeron, SkylarkDuQuesne
The LensmanSeries
Triplanetary, FirstLensman, GalacticPatrol, GrayLensman, SecondStageLensman, ChildrenOfTheLens, and in the same Universe, MastersOfTheVortex
The SubspaceSeries
SubspaceExplorers, SubspaceEncounter (posthumously compiled and edited from multiple sources)
The FamilydAlembertSeries with StephenGoldin
TheImperialStars, StranglersMoon, TheClockworkTraitor, GetawayWorld, Bloodstar Conspiracy (aka AppointmentAtBloodstar), ThePurityPlot, PlanetOfTreachery, EclipsingBinaries, TheOmicronInvasion, RevoltOfTheGalaxy
Single Works by E.E. 'Doc' Smith
TheBestOfEESmith, MastersOfSpace, SpacehoundsOfIPC, TheGalaxyPrimes
TheBestOfEESmith has the following short stories
ToTheFarReachesOfSpace (excerpt from TheSkylarkOfSpace), RobotNemesis (with E.E. Evans), PiratesofSpace, TheVortexBlaster (excerpt from MastersOfTheVortex), Tedric, LordTedric, SubspaceSurvivors, TheImperialStars, and TheEpicOfSpace (EEDocSmith on his writing style and methods)
Works by other authors in the LensmanSeries Universe
TheDragonLensman, LensmanFromRigel, Z-Lensman by DavidAKyle
NewLensman by WilliamBEllern