There are some good websites for Sligo, see a posting recommending some websites there. They come after yours.
Look to the census www.census.nationalarchives.ie
for the names you have and find where in Sligo they lived in 1901/1911
I have a CD set that I bought from the latter day saints, its no longer available and now the website replaces it.www.familysearch.org
The CD sticks and freezes my computer and some letters no longer work the "C" in particular and I'm sure that is why it is no longer available:
I have Boland birth records for Sligo from 1815 up to 1875
so if you have some names I will give it a try.
The Fenaghty records are from 1866-1873. Feely just a few from 1815-1852, jumps to 1865-1875.
Also have Church of Ireland marriages 1845-1862.
Easky back in the year of Griffith Valuation 1858:
Easky was a Village and a Parish as well as a townland in the Union of Dromore West (within 12 miles of named town)
Feeny 244 in Sligo, Easky 15
Fenaghty 10 in Sligo, Easky 7
Boland 75 in Sligo, Easky 9
Feely 23 in Sligo, 0 in Easky
Cogans 20 in Sligo 0 in Easy
The last two could easily be in other parishes within the Union of Dromore West.www.askaboutireland.ie
is a good source of Griffith Valuations with details such as landlord, size of land and what is on it, what Poor Law Union it belongs to and you can
see the neighbours.
National Library, Dublin the website will give you what processes you need to go through to see the RC microfilm for a particular parish. You can also see a genealogist to tell you what to look for. Dates and hours on the website and what times it is open, some evenings late but depending on what you are looking for eg: Estate records are in manuscripts and these are keep in storage and often have to be ordered up individually and returned before closing time.
It takes much longer than you will think. Certainly not a job for a couple of hours, set aside a full day at least, two if possible.
Make sure you have a digital camera. If RC and want to see
the Parish Priest make sure you make an appointment ahead of times, churches are not left unlocked any more and many of them have several parishes to cover. Worst case scenario
is no access but if you prepare them for your visit you will be better off. You need to remember they probably get thousands of visitors a year taking up their time so they aren't always happy campers.
If you contact local residents that have the same name as you are looking for they might ease the way. You can do this before you go by writing letters to residents in the area or taking their phone numbers with you.
A digital camera is important for gravestone photo's, a cloudy day will get you better pictures. Some inscriptions are in really bad shape so take along some white tissue paper and a black wax crayon to take a rubbing.
I've visited Sligo unless passing through on a tour but I understand they have some great Standing Stones such as the Carrowmore Megalithic Cemetary.
Just outside Dublin is Newgrange or Bru' na Boinne'. A fantastic stoneage passage tomb older than Stonehenge and the pyramids at Giza. I just took the bus from the Tourism Office in Dublin or you can take a car and the staff then take you by their bus to the site. A fantastic sight to see.
Take the Black Cab tours in Belfast to see the murals. Well worth a visit.