i have had a gas fire removed and would like a log burner putting in place the chimney has a liner ,do i need to have the chimey relined and if so any idea of the cost

You will need a new liner, gas and solid fuel are completely different liners. Costs of liners from stove shops about £900, you will get them half that price via Fleabay, beware of the cheap imports. You do realise this is notifiable works and although you can do these works yourself, by paying the council fee and fitting accordinaly, you will be better of using a Hetas registered installer, he will organise every thing, getting on a roof ladder with a 5m stainless steel snake on your back is not for the faint hearted.

Agree with everything BJD says. Use a HETAS installer, its far less hassle and you can be confident the job is done to the correct standards and is safe. Average cost for lining and fitting your stove (including register plates etc) is about £900. Kind regards, Martyn