Hiya Darren
I would go for a 13' 'waggler' rod - ie a rod without a spliced tip, so you've got sufficient power to handle the tench.
As regards the type of rod it all depends how much money you've got to spend - both Shakespeare and Daiwa do some excellent waggler rods for around the 60 mark. (I think there was one reveiwed in this weeks AT)
If you've got a bit more money to spend, check out the Drennan DRX range, I've got one of their 'Power Waggler' rods and for fish up to four or five pounds they're ideal.
The only real way to make a decision is to try plenty of different models - I can't really explain it but sometimes when you pick up a new rod it just feels 'right'.
Tight Lines
Simon