Erhm, it wasn't really necessary to make an entire thread about it, but I suppose...
:
Recommended Natures:
Typically Calm for the majority of Stall/Support sets, Admanant for Physical Sweeping, and Modest for Special Sweeping.
IV spreads vary from set to set, though for the Sweeping sets you want to max out Atk/Spc. Atk (whichever type of attacks you're using to sweep), put down 60 HP, and channel the rest into speed. The rest of the sets revolve around balancing Spc. Def, HP, and Speed. In order to get a more accurate idea of what they are, I suggest you look into Smogon University. In fact, Smogon likely covers all your questions concerning Ludicolo.