stats count host. Below search only returning "Server and Count" not the Desktop.
index| dedup host | eval "Type"=case(host=="xxx*","Desktop", host!="xxx*","Server") | stats count(host) by Type | rename count(host) AS Count | table Type Count
Need two row with Server & Desktop. If the host name starts with xxx its Desktop else its Server with count displayed
eval "Type"=if(match(host,"xxx.*"),"Desktop" ,"Server")
You can use match command like above.
http://docs.splunk.com/Documentation/Splunk/6.1.4/SearchReference/CommonEvalFunctions