The quickest way to check whether a public website still accepts the insecure SSLv3 protocol is the free Qualys SSL Labs Server Test. Enter your hostname and it reports every protocol and cipher the server supports, including SSLv3, along with an overall grade.
If SSLv3 shows as enabled, disable it on the server. See my posts on disabling SSLv3 in Microsoft IIS and the SSL 3.0 information disclosure vulnerability.