You cannot play GAA. The GAA is an organisation, not a sport. It governs a number of sports including Gaelic Football, Hurling, Camogie, Handball and Rounders. The rules of those sports are all different.
For the majority of players, it is the county that they are born and live in. Players themselves don't choose to play for a county as such. Players usually play for their local club. Each county has many clubs. The best players in those clubs are chosen to play for the county team by the selectors for the county teams. So the majority of players end up playing for their own county. Even if a player moves to live in another county, they will normally still want to play for their own county. It is a matter of pride and identity, in the same way that many sports people will want to compete on the national team of their own country, if they are selected to do so. They will do their best to get to the level to be able to be chosen. GAA players are the same. They want to play for their the county that they come from.
A full set of rules, like in any sport, are complex. See the link below for more detail. Also check the videos listed.
The GAA is an amateur organisation so GAA players and managers do not get paid. Many would all have their own jobs or be students, and their GAA activities are basically done in their own time, in the same way that many people are involved in sports. Players and managers do get expenses and occasionally some payments.
Some see it as representing Irish culture which they do not want to be part of, mainly in Northern Ireland. However, many Protestants do play GAA and there has even been a President of the GAA who was a Protestant. Also, the Sam Maguire trophy, the most important trophy in Gaelic Football is named after a Protestant. He was very much involved in the GAA.
The GAA encouraged people to play Gaelic Football and Hurling, Ireland's two main sports, and some other sports. They did not encourage people to play other sports such as soccer and rugby, because they were seen as foreign sports. The rules that banned people playing these other sports was removed in 1971.
No. GAA clubs welcome all members of any nationality. The GAA is an Irish organisation and it is found around the world where there are large groups of Irish people, so members are mostly Irish, but there are many members that are not from Ireland.
The GAA is the largest amateur sporting organisation in the world. Many people are playing GAA matches, both Hurling and Gaelic Football and other GAA sports. Gaelic Football is the most popular sport in Ireland. Last weekend one match in Dublin had a bigger attendance than the Superbowl did, by about 9,000 people.
Paying the players would ruin the game's heart and ethos. GAA players play for the love of the sport and for their local people, from where they come from. This means they play with more intent. The only time professional sports people have that kind of motivation is when they play for their country. In professional sports, players don't have a real connection to their team, as it is just a job, and they could be playing against that team if they change. They only have that sense of duty and belonging when they are playing for their country. It would not be possible to sustain a professional game, because of the amount of players and teams is so large in a small country. Many GAA players have jobs anyway, so they are playing for the love of the sport, not to earn money. The only thing they should get is expenses, and support if they get injured and are unable to work in their normal jobs. For these, and many other reasons, the GAA should not pay its players.
Anywhere there is an Irish community there are possibly some GAA clubs. If you check the North American GAA website, then you may get more information for your area.
Helping the lowest levels of the GAA in terms of the clubs and their facilities. This is the base of the GAA. The network of clubs, over 2500 in Ireland alone, are where the GAA derives its strength. It is built on the clubs. They are the root of the organisation. The ordinary people that run these are what make the GAA what it is, so it is important to support them. So a lot of investment goes into the clubs to help them as they are the grassroots of the GAA. Without the clubs the GAA would not exist, so money earned within the GAA is needed to keep them going.
Adding together Hurling and Gaelic Football titles won in all grades, Cork would be the most successful county in the GAA. As to which county is the best, that is a question that could be debated by many people.
Rathmore, Gneeveguilla, Killcummin, and Glenflesk.