Sure,
Just write in to your local tax office and claim the expenses against your tax for the relevant years ( I think there is a limit of 7 ?). Remember to use the words "wholly, exclusively and necessary". If you have them, send in copies of the receipts (if not don't worry, although you might be asked for them subsequently).
If you are a higher rate tax payer you should be submitting a self assesment return every year. This can be as the standard inland revenue form sent out to you from your tax office, or as an online return for which you need to register. There are boxes within these returns to claim for expenses incurred in connection with your employment. Once completed the tax liability is calculated or adjusted so that your liability is reduced or if applicable a refund is applied.
If you have any questions, ring your local tax office and quote the PAYE reference number shown on your last P60 or wage slip and or your own National insurance number. They will be able to give you better guidance. If you don't know your local tax office call your wages department and they will be able to tell you.