Your nearest airfields are going to be Wolverhampton, Coventry and Wellesbourne (near Startford upon Avon) all of which have flying training organisations. I suspect Wellesbourne may be the cheapest option but you'll need to do some research. Wellesbourne has the best cafe in my personal opinion
and has two runways (the short one is closed on Saturdays for a market). Coventry has full ATC which is both a good thing (from the point of view of getting used to it) and a bad thing (when a 737 is in circuit and you have to wait around burning money). Wolverhampton has three runways and both Wolverhampton and Wellesbourne are busy enough to give you plenty of practise mixing it with others.
I've done far more flying at Wellesbourne that the other two so I may be a bit biased, but they seem a bit friendlier and there's four fixed wing training organisations to choose from. One (Wellesbourne Aviation) has just been taken over by Cabair which may or may not be agood thing but I'd probably go for either South Warwickshire or Pilot Flight Training. One of our friends has recently got his PPL with Pilot Flight Training and they seemed very flexible and helpful possibly because they're not very big. The aifield website is
www.wellesbourneairfield.com and has links to all the training organisations.
Happy aviating