Hi,
Base on your description, you want to set the same url fot the sitemap node, right?
There is not allowed the same url in the sitemap file, but you can add some different querystrings for the url to distinguish the URLs.
For example:
<siteMapNode title="Home" description="Home" url="~/default.aspx" >
<siteMapNode title="Printers" description="Printer Service" url="~/printer_service.aspx">
<siteMapNode title="Warranties" description="Extended Warranties" url="~/ext_warranty.aspx" />
<siteMapNode title="Maintenance" description="Maintenance Aggrements" url="~/maintenance.aspx" />
<siteMapNode title="ASP" description="Alternative Pricing" url="~/asp.aspx" />
<siteMapNode title="Block Time" description="Block Time" url="~/block_time.aspx" />
</siteMapNode>
<siteMapNode title="Computers" description="PC Service" url="~/pc_service.aspx?1=1" >
<siteMapNode title="Warranties" description="Extended Warranties" url="~/ext_warranty.aspx?2=2" />
<siteMapNode title="Maintenance" description="Maintenance Aggrements" url="~/maintenance.aspx#" />
<siteMapNode title="ASP" description="Alternative Pricing" url="~/asp.aspx?4=4" />
<siteMapNode title="Block Time" description="Block Time" url="~/block_time.aspx?5=5" />
</siteMapNode>
</siteMapNode>
Hope it helps.