SQL 2005 Monitoring memory use - setting up an alert

Note:  This is for SQL 2005

Im following this example

http://technet.microsoft.com/en-us/library/ms176018%28v=sql.90%29.aspx

It mentions using these counters, but what Object did they select? 

• Memory: Available Bytes
• Memory: Pages/sec

I cant seem to find those counters in the lists for any of the available objects.

The image below, is what I see when selecting the Object "SQLServer:Memory Manager"

I think the article above is talking about using Perfmon?