Its usually handy to have a parish to be able to check what years the parish registers have survived.
The only on line website is a pay for record, not for profit foundation: www.rootsireland.ie
You can check without knowing any more information than the name. Eg: you would search for
Elizabeth McGurk born 1805 (+/-) this then will give you any Elizabeth's born within that time from in Sligo. This would give you the father's name, the mother's name and maiden name and a parish.
Bridget is fairly common so go with Elizabeth first. Once you have both parents names you can check for all siblings.
There are records for the Church of Ireland, St. John's from 1801-1900 for bm&d's
Sligo from 1831. Also there are Methodist and Presbyterian circut records from 1801.
The Tithe's were a tax for the Church of Ireland, imposed on all. 1823-1837www.genealogy.nationalarchives.ie
No McGurk's listed (could be spelling) Note: McGuirk
McGinley, Michael, Parish Kilmactranny, Townland Cloughglass X 2
McGinley, Hugh, same info
McGinley, ______, same info
There are no McGinley's in the Griffith Valuation - could be spelling.(note many in close Counties, Donegal, Tyrone, Londonderry and can be spelled as McKinley, which would make it very difficult.
Tried variants for McGurk and found 1:
John McGuirk, Parish of St. John, Townland Abbeyquarter South, Town of Sligo, Poor Law Union Sligo
tenant of Peter Conlisk
#23 Castlestreet - a house
Tried varients for McGinley - none.
1846 John McGuirk, 34 Castle Street, Sligo - Hairdresser
1870 John McGuirk, 28 Castle Street, Sligo - Hairdresser
1881 John McGuirk, 22 Castle Street, Sligo - Hairdresserwww.igp-web.com
both these resources have a variety of information depending on the counties, sometimes parish records and gravestone inscriptions
Sligo Telephone directory has 4 McGinley, 1 in Tubbercurry and also 1 only McGuirk
Addresses given are sufficient for mail delivery, no postal codes required