I wish to transfer from an old cash isa to a current isa

Hi geoff8
You will find a list of ISA providers on this site below:
http://www.money.co.uk/savings-accounts/cash-isas.htm
You just need to find a suitable one that will accept transfers in.

You will need to check if if M&S accept transfers in. If they do then just fill in the required forms and leave it up to them to sort out.

NCBS has an ISA that accepts transfers and gives 3.7% - even though it is fixed for 3 years you can , with 90 days notice, withdraw money or close the account at any time without loss of interest. That is what makes it so attractive - its almost an easy access account.
We have just transferred some of our ISAs without any problems. Best hurry as it may get over subscribed.