I've tried nic handles lately, and they seem to universally return errors about invalid keys for me. My registrar will let me display all *my* records by nic handle, but it's only records on which I am listed as a contact, and I have to be logged in. (Real useful - I know what domains *I* own.) Even that won't stay complete if I ever register in a TLD they don't handle.
you can easily search the contact info, but i think you can see the domains registered by the user for last 6 months ( just not sure ) in the whois of networksolutions just type "name lastname,firstname" excluding the quotes , for examples type " name gates,bill " ...i dont expect you to see microsoft.com here ... but still give a try... after all practice makes men perfect. ...although i doon know about women. :)