It is an absolute mistake to visit just the more famous Argentinian side of the falls skipping the Brasilian side.
Here some practical tips you may find useful to visit the Brasilian side of the falls:
I. The best airport to arrive to visit the Brasilian side of the falls is Foz do Iguaçu Airport. From there a cheap, local and frequent bus offers a reliable service straight from the Airport to the gates of the National Park (Brasilian side). Normally flights are also cheaper than the one directed to the nearest airport on the Argentinian side (Puerto Iguazu Airport)
II. If you are planning to visit also the Argentinian side of the falls, the best thing to do is land at Foz do Iguaçu Airport, visit the Brasilian side and in the evening move to Puerto Iguazu, spend the night there and visit the Argentinian side the day after. Which leads to the following suggestion.
III. Puerto Iguazu (Argentina) is a much nicer, safer and cheaper place to stay for the night than Foz do Iguaçu. This suggestion is not going to make me popular in Brasil but unfortunately there is no comparison, stay in Puerto Iguazu!
IV. Depending which is your country of residence to cross the border between Brasil and Argentina can be very expensive because of the so called reciprocal visa taxation (even up to a 100 US$ for just a day).
V. Travelling from Foz do Iguaçu to Puerto Iguazu is not as complicated as some taximen will tell you. Just take a bus to the border. Some buses will wait for you when you have your passport stamped, some others will give you a ticket to present to the driver of the next bus coming, as they will not wait for your visa. In any case there is a bus stop around 200 meters after the border, just walk there and take the first bus.
VI. There isn't a combined ticket to visit both sides of the falls.
VII. Bring some waterproofed clothes if you are planning to walk to the center of the falls... which is a great experience I absolutely recommend you!!!
Before to visit watch our video about the Iguazu Falls (Brasilian side) and read about the history of the falls. Read also about the Argentinian side of the falls.