Angels have been a part of the Lords work since the begging of time. Here is a collection of stories of angels administering to people in modern day.
Angels Protecting the Gold Plates and the Journey to Fayette. During the translation of The Book of Mormon, there were many people trying to steal the plates from Joseph Smith, here is an account of the angelic protection of The Golden Plates
Women Witnesses of the Book of Mormon. Mary Whitmer was shown the Golden Plates from an angel one day while she was out at the barn. You can read her story from the link above.
David Whitmer’s Miracle. David Whitmer's angel story is one of the many amazing stories in Church History. David was willing to help with the translation of The Book of Mormon, but he needed to finish he work, getting his crops in. He went out to work on his crops and it was all done, and he sister said she thought David had hired help to because she saw three men out working on it. Read the story from the link above.
Founding Fathers and the St. George Temple. Wilford Woodruff was visited by the Founding Fathers in a dream, saying for three nights he had been awoken by these men, asking Wilford to do their temple work for them. It is a very powerful story, link above.
Angels Ministering, Cardston Alberta Temple. This story is about a woman getting sealed to her children in the Alberat Temple, and the man sealing the little family could not move on because he kept hearing a voice.
Logan Temple Collection of Stories. The Logan Temple is full of stories of visitation of angels. Here is a compilation of stories about the Logan Temple.