a couple of resistors forming a voltage divider will do the trick. For 5 to 3.3 I use 2 10K's in series to cut the voltage in 1/2 would give a max analog input of 2.5ish volts.
If you want to tweak the resistor values here is a divider calculator, voltage divider link a handy link to have around
For more voltage divider info use the words "arduino 5 to 3.3 voltage voltage divider" in your internet search engine.