Hi SAB,
The Teme upstream from Tenbury Wells is supposed to have decent fishing? grayling, trout, etc
Near Ludlow you have both the river Onny and the upper Teme, the best idea would be to contact the local tackle shops in Ludlow, I'm sure they will know and sell day-tiickets for the waters available.
http://www.ludlowtackle.com/
There is even an Orvis Store (U.K.) in Ludlow! They would be my first call!
Orvis, 8 High Street,Ludlow, Shropshire SY8 1BS, Phone: 01584 877876
Geographically, Ludlow is on the A49 (as the crow flies - pretty much on a direct line) from Tewekesbury to Shrewsbury. If you are diving that way, watch your speed there are plently of mobile / speed traps on the A49.