GTA 3 does have a lot of vehicles that you can choose from. However, there is one vehicle that is infamous because of it's obnoxious little jingle and the way it looks.
The Mr. Whoopee ice cream truck is a car that is really hard to find. Although you do get to make some money by doing missions it has to offer, it's a wonderful car to drive (provided you can ignore that jingle.)
Where to find the Mr. Whoopee Ice Cream Truck in GTA 3
You can find the Mr. Whoopee Ice Cream truck in two possible ways. You can either scourge the streets and bank on your luck to come across one. Or you could wait till you get a mission that allows you to drive this truck.
When it comes to finding this truck on the streets, you can come across it near Chinatown, Saint Mark’s, Portland View, Cedar Grove, and Rockford.
Alternatively, if you follow the road from Luigi’s place to the main highway going down the hill, you have a chance of coming across one such truck here as well.
If you're lucky enough, you can find a Mr. Whoopee is parked in Wichita Gardens or the Staunton View Picnic Area in GTA 3. However, it's a rare sight here, so it would be best to look for it near the streets mentioned above.
However, once you have collected all of the Import/Export vehicles, you can find a Mr. Whoopee parked in the garage at Portland Harbor. This, however, is very time consuming. so you're technically better off off searching in the first island if you're looking to add it to you're garage early on.
Finally, you do have a sure shot of getting your mitts on a Mr. Whoopee Ice Cream Truck. All you need to do is wait till you get the mission "I Scream, You Scream." A payphone offers this mission. Once you've got this mission, you can fail the mission and park the truck in your garage for further use.
And that's how you get the Mr. Whoopee Ice Cream Truck in GTA 3. Good luck finding one. Just don't get annoyed by that weird jingle they have.