Our Club takes in new people at any time of year, of any ability. As the coach for the beginners (mostly women) i usually take them out at the back of the group and let newcomers run at their own pace - if they drop back, i drop back behind them. If they go ahead, i keep an eye on them to make sure that they aren't alone. one of the other ladies will keep with them.
Our basic rule is: No one is ever left alone at the back. We usually find we have newcomers who have done the race for life and want to continue. Most clubs have some sort of beginners group. They may start at certain times, or they may be incorporated into other groups.
Have a look on www.runtrackdir.co.uk for your local club and give them a ring.
If you post your area on here, i'm sure someone will be able to offer you advice on local clubs.