Hi Annette,
You could try posting as much information as you can on your relatives. Inlude names, dates, marriages, emmigration information etc....The more information that you post the more likely it is that one of our volunteers will be able to assist you.
A few sites that may be of assistance to you are:
http://www.irishtimes.com/ancestor/browse/
http://freepages.genealogy.rootsweb.ancestry.com/~donegal/
http://www.irishroots.com/id4756.htm
I wish you the best of luck with your search.
Kind regards,
Genealogy Support
Ireland Reaching Out