OK, I'm afraid you're gonna have to be a bit more specific if you want some better help.
I suggest you start by having a look at this thread:
http://apolyton.net/forums/showthrea...threadid=59216
There are links in there to lots of good things that people here have written on Civ3 strategy. Maybe those will help you.
Otherwise you should post a savegame file from a game you're in the middle of and have become stuck. People are usually very happy to take a look at it and suggests improvements you might want to make to your strategy.
Also, what difficulty level are you playing at?