There are indeed a lot of choices out there. Do you have a budget in mind, and do you need any special features like assignable extra function keys, or the ability to easily control volume or other functions from the keyboard? That might help you narrow it down.
If it is just for typing, will you be using it all day or just occasionally? I use mine all day and for gaming at weekends, and prefer a keyboard with mechanical switches over a membrane or rubber dome keyboard. Mine is a Logitech G513, which has tactile switches (with a tiny ‘bump’ feel) and includes an excellent plush wrist rest, but is much quieter than other mechanical keyboards.
You might prefer something completely different though, and there’s nothing wrong with a basic Microsoft or Logitech keyboard.
If you fancy something more special though, and if you can get to a computer shop and try a few out that might help give you some ideas. Online retailers like Scan, CCL and Aria pc have lots of choices, many with reviews from users too. Curry’s might have stock you can try the feel of, but I wouldn’t buy from them personally.