Have a look at this mate:
http://www.anglersnet.co.uk/rigs/carprigs.htm
Knots are obviously the most important part, learn the Grinner, Palomar and Knotless Knot, learning these will give you enough knowledge to tie an effective carp rig. Do a search on google for 'carp rigs' to find more.
Ohh, and learn a good loop knot too.