For free stuff, a couple of good places to start would be
Insimenator.net and
Mod The Sims 2.
And of course, the sites that have posted update notices here are alive and well. Look around at the threads in the
Ultimate Sims List Additions and Corrections forum and
Sims 2 Fan Sites Links and Updates forum.
Beyond that, try surfing around the
Ultimate Sims List. We're still pruning out closed sites and you'll hit a lot of Sims 1 sites, but with a bit of mining you'll find the gold in them thar hills! If there's a legitimate Sims fan site out there that isn't in
The List, it's because no one has told us about it yet!