Some good county specific sites most of which are independent rather than official gaa ones.

Armagh:
http://www.orchardcounty.com/ - Armagh site, active forum.

Cork:
http://www.rebelgaa.com - Very high quality site covering all Cork GAA.

Dublin:
http://www.hill16.ie/ - Official Dublin Site.

Kilkenny:
http://www.kilkennycats.com/ - Kilkenny hurling fans, mostly an active forum.

Laois:
http://www.laoistalk.com/ - Laois news and forum

Tipperary:
http://www.premierview.ie/ - Tipperary hurling supporters website.

Waterford:
http://deiseach.wordpress.com/ - Regular news from a Deise blogger.