UKIsearch.com is a good site for Co Tipperary ancestry research. It has many links to databases and records and they are all on this one site. The site covers Ireland, Scotland, Wales and Britain. It also has an International section.
County Tipperary Roman Catholic Records at Rootsweb lists the Co Tipperary Civil Parish name and next to it the Roman Catholic Parish name and when the parish began. This makes tracking ancestors in Co Tipperary a little easier.