Capt,
You should contact the school you sat your exams with. They will have the centre number and candidate number, and in some cases will have copies of your results so could send a certified letter. If not, contact the relevant exam boards and ask - although they will probably ask for your candidate number and centre number. Unfortunately you cannot get certificates, merely "Certifying Statements of Results". The popular boards are shown below:
Edexcel -
http://www.edexcel.org.uk/VirtualCon...ic_awards_.pdf
AQA -
http://www.aqa.org.uk/admin/library/AQA-EXAMRECORDS.PDF
OCR -
http://www.ocr.org.uk/Data/publicati...nt_results.pdf
If you can't remember which board you sat with, best ring them and ask what to do.
Horgy