I currently have two books I am trying to find
The first is a young adult book series that starts off with a soldier being asked to deliver a magic ring to an old man/wizard. Along the way the soldier discovers that he can use the ring to do magic. He uses it to rescue a dragon trapped in a cage by shrinking it. After some adventures caused by a lot of people really wanting the magic ring, he finally gets to the old man/wizard. It is then reveled that the magic ring though powerful/dangerous only has one kind of magic, so all the other things he did must have come from him he then becomes the wizards apprentice. In the next book the wizard dies and leaves him all his power (temporarily his memories and personality) and for some reason a dragon queen does the same thing making him a very powerful wizard. He then decides that he would like to find out more about dragons (the dragon queen was hoping to create an ambassador by leaving him her power/memories)and so he goes with his dragon friend from the previous book who is from a dragon troupe in which the queen is still in a egg. Things then get more complicated with him learning about dragon culture and history and and trying to start peace between humans and dragons.
The second book is for a slightly younger audience and I think it is a newer book. In it a girl accidentally finds out that her new neighbors are not from her world when a thief escapes from a doorway they guard and gives her a strange egg then dies. The neighbors take her to their home and she learns that they are aliens that guard the entrance of portals to other worlds and that the thief was forced to steal the egg by bad guys who wanted it, and that the egg is now somehow bound to her and they cant remove it from her without it dieing. The egg is a very special symbiote that very many want but few are allowed the privilege of getting. She learns that the creature inside the egg chooses its form depending on what its host is. The book ends with the creature deciding to take the form of the girls shadow. Solved: Thresholds' by Nina Kiriki Hoffman