Neely (any spelling) in Mitchelstown area

Hi. I've recently learned that our NEELY family, living in the Holycross area of Tipperary in the mid-1800s, actually came from the Mitchelstown area of Cork.

What is the best way for researching the Mitchelstown area for the period of 1800-1875 ?

Any other Neely researchers out there ?

Thanks.

Nancy