I am having trouble finding a rule that says anything about restrictions with epic magic Items being used by non-epic characters. That's it I just wanted to know if there is some rule in a legit book about that. If you could list the book and page number that would be great.
A non-epic creature can employ an epic magic item
Neither the Epic Level Handbook (2002) on Epic Magic Items (123-50), the more recent SRD section on Epic Magic Items, the Dungeon Master's Guide (2012), nor the Magic Item Compendium (2013) in its handful of references to the Epic Level Handbook mentions any general prohibition against the use of epic magic items by non-epic creatures. Epic magic items have more prerequisites for their creation than their non-epic counterparts, and one epic magic item can easily exceed the entire expected wealth by level of a non-epic PC, but—so far as I'm aware—no rule prevents a non-epic creature that somehow acquires an epic magic item from using that epic magic item if the creature should otherwise be able to: the magic item's epicness… epicity… epicitude… that the magic item's epic is merely a classification based on, for example, the magic item's market price or total enhancement bonuses. Classifying the magic item as epic doesn't usually have an impact on how, if, or for whom (or what) the item functions.
(Some creatures may—by virtue of their statistics or class choices or Use Magic Device skill bonuses,—find some epic magic items (like, for example, epic scrolls) very difficult or impossible to use, of course!)