Although the simple pleasure of birdwatching can be enjoyed with no equipment at all, once you want to see more rare or shy birds you will need to find a way to see birds without them seeing you. Some of the things you will need for more involved birdwatching include:
Binoculars
Bird
Hide
Digiscopy
Equipment
Finnstick
You may want to visit the Cornell
Lab Birding Shop to see what's available!