In regards to the removal of permanent ink...the absolute best product on the market is called "Goof-Off" and comes in a yellow can (either spray or pour) stocked in the paint section of supermarkets. It works flawlessly to remove ink from plastic shrink wrap or cellophane with no ill effects. it removes price-tags and residue with ease. Even the metal security stickers and plastic box-like security tabs come off without a trace.
As for paper products, A little Goof-Off on a soft rag, dabbed on the inked area sucks the ink out right of the paper without damaging or discoloring the surrounding card surface.