try www.familysearch.org - should give a ref to pages giving addresses of all mormon family history centres
otherwise look up Church of Jesus Christ and Latter Day saints (possibly also as LDS) in your local telephone directory they will either host a FHC or refer you to nearest - the IGI will give you the film ref for parish reg (marriage) - the online wills index www.iomfhs.im will give you the film number for the will -