Best place in Shropshire for airguns at the moment is Morgans of Oswestry - Take the A5 to Oswestry, straight on at the Little Chef/Petrol station island and it's on the Industrial Estate on the left before you hit the town itself.
Best range of stuff, and best prices too. They match a lot of the mail order prices, which is pretty good for a shop in Shropshire! Pellet range a bit poor. Very busy store (they also do farm and building supplies) so service may be a bit slow.
Another shop in Oswestry town itself - very small, not great but good range of pellets, opposite the bus station, looks like a fishing supplies shop from outside.
There's Minsterley Ranges, at the Bog, Stiperstones. Mostly fullbore though, few air rifles.
One shop in Shrewsbury, on Belle Vue, avoid at all costs! Unhelpful and rather stingy rip off merchants.
That's all the ones I know.