The cider list in the programme is not as complete as it could be, they rarely are at beer festivals for some reason. I've done a little bit of detective work to put together a slightly more detailed listing, though again, you'll have to visit the pubs to find out where they are.
Broome Farm - Herefordshire
Gwynt-Y-Ddraig - Glamorgan
Hucknall Cider Co - Nottinghamshire
Millwhites - Hertfordshire
Rockingham Forest Cider - Northampton
Westons - Herefordshire
There may also be cider from Thatchers, and possibly something from Eve's of Kettering.