Links on Social Media
The Ryan Clan Association of Ireland Facebook Group
https://www.facebook.com/groups/268468327993304
The Ryan Clan Genealogy & DNA Forum Facebook Group
https://www.facebook.com/groups/RyanGenealogyAndDNAForum
Ryan Clan of Tipperary & Limerick Facebook Page
Lots of history of the Clan from across Ireland
https://www.facebook.com/ryanclanoftipperaryandlimerick
Books
Here are some books about the history of the Ryans:

The Ryans of Tipperary and Limerick – Their Origins in Owney and Owneybeg
By Brian Kennedy
RYANS – THE IRISH KENNEDYS (weebly.com)

The Ryans of Tipperary and Kilkenny – Their presence in Kilnamanagh, Eliogarty, Ikerrin and parts of Clanwilliam, Crannagh, Galmoy and Middlethird baronies
By Brian Kennedy
RTK – THE IRISH KENNEDYS (weebly.com)

Ryan (Irish Family Names)
By Daithi Ó Hogain
Ryan (Irish Family Names): Amazon.co.uk: O Hogain, Daithi, Thew, Peter: 9780717135561: Books

War, Politics and the Irish of Leinster
By Emmett O’Byrne
Gives a good overview of the political situation in Leinster where the Ryans of Idrone were located. Only touches on the Ryan briefly in passing.
Four Courts Press | War, politics and the Irish of Leinster, 1156–1606