I am getting the "The Server tag not well formed error". Please see the below code:
<ul id="wizHeader">
<asp:Repeater ID="SideBarList" runat="server">
<ItemTemplate>
<li>
<asp:LinkButton runat="server" CssClass="<%# GetClassForWizardStep(Container.DataItem) %>" Font-Bold="true" ID="SideBarButton" OnClick="Step_Click" Text="<%# Eval("Name") %>" ToolTip="<%# Eval(ID) %>"></asp:LinkButton>
</li>
</ItemTemplate>
</asp:Repeater>
</ul>
You can't use <%# inside of server controls' attribute.
So if you want to use a LinkButton inside of the Repeater, you have to bind the attributes in code-behind using the Repeater.ItemDataBound event.
Example from MSDN: http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.repeater.itemdatabound(v=vs.110).aspx