Does your stone or marble need to be within the city's radius to get the speed bonus on producing a wonder? I didn't think so before, but I've read a couple posts that imply that they do....

I don't think so, I think you just have to be connected to it by a Road or other Route.

Yeah, it needs to be within your cultural boundaries first (so you can mine it), but doesn't have to be within the workable tile radius, and then it needs to be connected via road or river (coastal might work as well) or both to the city trying to build the wonder.

Right. This isn't like Civ3 where you could build a colony. Nothing outside of your cultural radius can be used. And even then you need a road to it AND a mine over it. In Civ3 it was enough just to build a road to it.

Incidentally, I like this change as I felt it was a bit unrealistic in Civ3.

Does your stone or marble need to be within the city's radius to get the speed bonus on producing a wonder? I didn't think so before, but I've read a couple posts that imply that they do....

No, just within your cultural boundries, improved and connected by road. This applies to any resource - food, horses, gold, etc. Also you can send work boats to any water resources within your cultural boundries to get the health benefits.

HTH