I bought a few expansion packs a while back... ;7;
EDIT: to answer some questions... as of now, I have these expansion packs: generations, ambitions, late night, and show time
Please don't ask me where to download Sims. I bought my copy, but I bet that there are many pirated versions of it out there on the interwebs.
Most of the custom content I downloaded came from My Sims 3 Blog, RAONJENA, Lemonleaf, XM Sims, Mod The Sims... I can't exactly remember all of the links of course. I mostly blindly downloaded everything I found to be of interest.