I read in the soccerage Kewell was essentially "tapped" hence why he moved to Liverpool for 5m pound, 2m of which went to the agent.
If that is found true, I think FIFA should investigate the situation and fine Liverpool, Kewell's agent and Kewell substantial amount of money for a breach of regulation, if I correctly remember forbids such conduct.
While FIFA intends to kick out racism, and violence on the pitch, IMO, just as alarming matter is stamping out illegal and admittingly annoying transfer activities by the agents and clubs.
This is not just confined to EPL. I am pretty sure basic deal was agreed between Beckam and Real way before the deal was concluded, and Figo himself admitted he agreed to join Real during the Perez's election campaign hence he was illegal tapped.
If teams want to buy players, contact the respective club first and once the deal has been agreed then they can talk to the players. As for the agents, if they are found trying to sell off their agent to other clubs in such manner that is detrimental to the team, then they should be evicted of their licensce, subject to heavy fine, and ban to manage players for couple of years.