This was how I used to do it.
Put an advert in the local newsagents window.
Leaflet distributors required, must be over 13 yrs old, £3 per hour.
Usually get paper lads / girls who are interested.
Take them out on a saturday morning to a large, modern housing estate.
Set them off in pairs, with a street map. Take mobile phone numbers to keep in contact.
Drive around in my car keeping an eye on them and giving out more leaflets / instructions.
Usually 3 hrs is enough.
The knack is to take them to an area that they dont know that well, so they cant just nip into a mates house and hide for an hour

4 kids at a time is easiest to manage, any more and it gets to be a hassle watching them.
4 kids @ £3 per hour x 3 hrs = £36. Usually managed to get 1000 to 1200 leaflets out in a morning.
And all I did was sit in the car, listening to the radio

regards
Chris