This is probably the most famous birdwatching place in Australia...
I have stayed here three time; twice on my own, and once as a guide with a group.
O'Reillys is located near the Green Mountain section of Lamington National Park. This is south-east Queensland, just slightly north of the NSW border. It is surrounded by subtropical rainforest.
The hotel itself sprawls over a large area, and includes a range of accommodation; there are separate villas, smaler rooms, and a camprgound. There is a restaurant and bar in the hotel, and another cafe in the large gift shop complex.
O'Reillys is about a two hour drive from Brisbane. Don't use Google maps, as it may tell you to go via Duck Creek road, which is a small track unsuitable for cars, and usually closed. Go via the town of Canungra. The last section from there up the hill is a small road with many bends. It is sealed and has great views, but be aware of traffic coming in the other direction, especially locals who may be driving very fast.
There is a variety of different walks.
The boardwalk from the lodge is great because it is easy and good for birds, as the guides feed the birds here when they do their early morning walk. You might see Whipbirds and various scrubwrens.
If you continue from here, there is a canopy walkway, unusually open all hours. There is also a botanical gardens here.
Past this begins the border track, which connects this lodge with another lodge called Binna Burra. This is a very long walk, but you can walk part of it to get some great views of subtropical and then temperate rainforest. In the first few hundred metres, if you are quiet, you have a good chance of seeing Logrunners.
From the lower grounds of the lodge are various walks. There is a great waterfall. One of the best spots is Mick's Tower, which is often quiet and good for birds.