Can anybody suggest any good walks or books/websites for South Wales?

I have recently moved to Cardiff and am a keen walker. In london I ran a walking group that followed the 'Time Out' books 1 and 2 which I found very good, giving train times, suggestions and contact details for lunch, easy to follow directions inclucing comp references and good maps. Is there anything similar for south Wales area? I prefer to do self guided rather then led/ramblers group walks and can drive to the start of walks or take the train. Happy to do anything from 5 to 20 miles a day - suggestions for good walks or sites welcome. so far I have done Blorenge near Abergavenny, Rhossilli on Gower, Peny Y Fan, and other short walks around Cardiff Bay area. suggestions welcome - I miss Time Out! (but I don't miss London...) thanks"