Torry.net is the definative source for Delphi/Kylix/C++ Builder components. Check this before asking questions where to find component ZXY.
Delphi Super Page has a huge collection of components, applications etc.
SwissDelphiCenter has a large collection of tips.
We also have a mailing list. You can find instructions how to join and post messages at http://www.freelists.org/list/delphichannel.