The TServerSocket and TClientSocket components are a part of the 
'dclsockets100' package library.
 
Here are the steps needed to have them under component palette:
 
  1. From the Delphi IDE menu select Component - Install Packages,
  2. Click Add, in the Install Packages dialog,
  3. In the Add Design Package dialog, browse to your 'RAD Studio5.bin'
folder (for Delphi 2007) and select dclsockets100.bpl, then click Open.
  4. Click Ok. You're done.