Using asp.net menu control you can specify the images for menu controls
EX:
<asp:Menu ID="NavigationMenu" runat="server" CssClass="menu" EnableViewState="false"
IncludeStyleBlock="false" Orientation="Horizontal">
<Items>
<asp:MenuItem NavigateUrl="#" Text="Home" ImageUrl="~/Images/NewStyle/home.png" />
</items>
</asp:Menu>
More Info
MENU WITH IMAGES[
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