Which may already be in your ticket
Porfio_Rubirosa said:
But there is also a US$20 departure tax to be paid in dollars. All in all, your contribution to President Mejia's new houses and reelection will be $US30.
Charters: you usually pay at the check-in counter.
AA: The ticket has the departure tax in it UNLESS it was issued/paid for before the increase in which case you pay AA $10.00 at the check in , not $20. At least $10 will be in the price now.
CO: I am 99% sure Continental includes the DT in the price also.
Tourist cards are obtained at the little window to your right as you enter immigration hall and there is a BR cambio adjacent (also in the luggage area too).
If you are at MIA and checking in at the Caribbean counter they sell the tourist cards there and since there are a lot of little blanks to complete try to buy it where you depart so you can fill it out in advance and beat the lineups.
Canadian charter companies (for example, don't know US ones) like Transat and Skyservice include the card in your fare ( but not the departure tax, go figure) so you may be told to get one at the tour counter at your departure airpot and it is "free".
While the Hippo joke was amusing keep in mind almost all airports do this one way or the other, Toronto has had embedded departure tax for a long time and YVR makes you buy a coupon from an ATM for $5/$10/$15 before you board.
And $10 tourist cards are less than $100+ visas or the quaint Chilean practice of not requiring a visa, giving you free tourist cards but charging you US$60-100 for the life of your passport as revenge for charging Chileans for visa applications most of which are denied.