Brian,
The idea of people marrying locally is pretty sound. Before the arrival of the bicycle in rural Ireland (around the 1860s) nearly all courting was done on foot, and so you tended to marry locally. Often the girl next door. Literally, in some cases. Especially for farmers who couldn’t afford to spend much time away from the farm. Of course there were plenty of exceptions eg people in mobile occupations such as soldiers, policemen, stonemasons, carriers. But in rural areas, it was common to marry “within an asses bark” of where you lived (ie the distance an ass’s call would travel. Half a mile, if that.) That’s how I heard it described once.
The other thing is that folk who were farmers didn’t move home much. You don’t spend 30 years improving the land, just to throw in the towel, move to another farm and start all over again. Wherever possible, farmers stayed put. Farm labourers on the other hand (a huge chunk of the population) were always moving about to follow available work. But if your family were brought up on a farm, statistically, they and their ancestors are likely to have been in the same spot for quite a long time.
Regarding records, the vast majority are held in PRONI. The original Church of Ireland records are sometimes held by the church, sometimes by the RCB library in Dublin and in a few cases by PRONI. If they still have them, you can consult the originals at the church. You need to make an appointment and there is a fee to pay which is usually £12 an hour, per church. On the other hand in most cases, you can consult a microfilm copy of the same records free in PRONI. So going to PRONI will save you both time and money. The PRONI church records catalogue (which is on-line) will tell you what records exist for each church, and where they are held if they don't have them.
http://www.proni.gov.uk/guide_to_church_records.pdf
For farm tenancy records, there was never any requirement to keep a formal record of who tenanted each farm. Some bigger landlords kept quite good records, often in estate ledgers. Some of those were sent to the Public Record Office in Dublin in the 1800s and early 1900s and were lost in the 1922 fire. Some were given to PRONI post 1922 and have survived. The thing to do is to search the PRONI e-catalogue for the landlord’s name and see what comes up. Likewise search under your own family’s name to see what it throws up. You can narrow the search by adding townland names or at least “Tyrone”.
If a landlord and tenant agreed a lease, there would normally be 2 copies, one held by each. In many cases, once the lease had expired, the 2 copies got thrown away. But in some cases at least 1 copy survived, either in the estate office or sometimes in some solicitor’s office, and these have often made their way to PRONI. So sometimes you will find a lease there. Another option is the Registry of Deeds records. From about 1709 onwards the Registry of Deeds (in Dublin) provided a service whereby you could send a legal document like a lease to them, and they would keep a formal record of it. It was a fairly detailed summary, called a memorial, and was entered into ledgers. The idea being that if the originals were lost and there was some need to refer to what had been agreed, this duplicate was publicly accessible. There was a fee for registering deeds, so understandably not everyone bothered but many millions of leases and other documents such as marriage settlements, mortgages, loans and some other more obscure papers are recorded there. The originals are in Dublin, but there’s a duplicate set on microfilm, in PRONI. You can search by townland and by name. It’s fairly time consuming but obviously worth it if you strike lucky.
The first fairly comprehensive set of land records were the tithe applotment records. Compiled in the late 1820s or early 1830s (depending on location) they list most land in Ireland, and who the tenant was. They were compiled for tax purposes. Some tithe records are missing, and some land was exempt eg church owned land, and so no records were kept for it. The surviving records are accessible on-line. In the case of Tyrone, you can find them on the Co. Tyrone link further down this message.
The next assessment was Griffiths Valuation. There was an initial valuation in the 1830s. These were recorded in notebooks which (for Northern Ireland) are in PRONI. They aren’t on-line, and you need to go in person to view them. They are in the VAL/1 series of records at PRONI. Then in the years 1848-1864, the Primary Valuation was compiled. That’s on-line on the Griffiths site. It lists many houses, as well as farmland. It shows you who the superior landlord was for most land, or if it was owned outright (as just 10% of land was in the mid 1850s) that is shown too. After Griffiths, changes were recorded in the Valuation Revision Books. They cover up to 1929. For Northern Ireland only, they are on-line free on the PRONI website. Not every home is in Griffiths. Houses of too poor a value to be worth taxing were ignored. And it only lists head of household. You rarely know who else lived there. So if folk were living with relatives, or were working as servants, they won’t be listed.
Statutory records of births, deaths & RC marriages started in 1864. Non RC marriages were recorded from April 1845. They are all held on-line now. You used to be able to inspect the originals at GRONI in Belfast but that has stopped to protect them from damage, and instead you have to view the originals on-line.
Records of baptisms, marriages and burials prior to those dates are patchy. The church kept them, if they were kept at all. Generally only the Church of Ireland kept any burial records but even they don’t appear to contain all burials. Where they exist, those records are in PRONI. Some graveyards also have burial plot records (ie details of who is in each grave). You need to enquire locally for them. But the further back you go, the less likely you are to get any. Most gravediggers were illiterate so paper records weren’t much use to them. Only a small number of graveyards have burial records for the early or mid 1800s. PRONI has some burial records, particularly for civil graveyards in and around Belfast.
Some graveyards have had their gravestones transcribed, and these are on-line on various pay to view sites. But many have never been transcribed.
Some countries have a system of county record offices, whereby records for that county are concentrated in that one location. Northern Ireland isn’t very big and so here the decision has been to keep most records in PRONI. Tyrone does not have a county record office. There is a local studies section in Omagh library, and that’s quite useful for background reading. For example there will be books describing what it was like to be a farmer in Tyrone in the mid 1800s, or what the linen industry was like. Old newspapers perhaps. But they don’t keep personal records as such.
I have attached a link to a website which has quite a lot of Tyrone records on-line. You might find it helpful.
https://cotyroneireland.com/index.html