I'm not a fan banning people or of the local community being told where known paedophiles live because this gives a false sense of security. Parents are much more likely to tell a child to avoid a particular person or people and then assume they're safe.
Children need to know that dangerous people can be anywhere. Not in a way that simply scares them but in a way that makes them aware that 'nice' people are not always trustworthy people and teaches them what to do if they feel uncomfortable with someone. I taught my girls the golden rules....don't wander off with anyone, I will never send a stranger to collect you no matter what he/she says and if you're worried shout as loudly as possible, "He's not my dad/She's not my mum!" as causing a commotion and attracting attention is often all that's needed in that situation. The final thing I taught them was where to hit a man if all else failed. Hit hard and run to the nearest shop, place where there were more people etc. As parents in the area we also arranged 'safe houses' where, if they were scared or worried about anything when out, they could just walk in without knocking.
Life would be easier if a paedophile looked like a sleazy guy in a dirty raincoat but it's not like that. They can be a parent, favourite aunt or uncle, a grandparent, in fact any family member, a family friend, a doctor, a teacher, a coalminer, a nursery assistant.....you name it. A paedophile looks just like anyone else.