Foclóir.ie, the New Irish-English Dictionary from Foras na Gaeilge, is an online dictionary with a number of features for integrating the dictionary in a browser or webpage.
The website Teanglann.ie is being developed to include dictionaries, grammar sources and a pronunciation database.
Information on the history of the Irish language can be found on the Irish Libraries' Ask About Ireland website and on Foras na Gaeilge's website:
Ask About Ireland: Stair na Gaeilge by Bríona Nic Dhiarmada. (English translation: Irish Language and Literature.)