Need rolling stock ideas

My first thought is circus cars.

You need some giraffe cars.

(And for everyone who was a Toys-R-Us kid, check out Geoffrey from Toys-R-Us on a retirement trip with Met & Yank from the Bronx Zoo and another giraffe who went through my last my layout in an anonymous manner.)

I'm with Pat.  You can never go wrong with gi-raffes.  

Of course, I may be ever so slightly biased... 

Mitch 

Yes, Giraffes are perfect!

How bout the Lionel Mickey and Minnie Mouse hand car?  Not rolling stock within a train, however none-the-less ... "amusing"... for your amusement park.  

Any of the Disney cars that were produced by Lionel.  

The animated cop and hobo car originally produced by Lionel and later reproduced by K line or Williams by Bachman? ( can't remember who did the reproduction.) 

Consider filling some of your empty flat cars or gondolas ( assuming you have some ) with Disney or other cartoon characters such as Donald Duck, Roadrunner, Smurfs, etc. .... which you may find at Target or Walmart.  They don't have to be scale.   You can even paint the flat and or gons in various bright colors for that amusement park flavor.  

Take a gander at your Christmas ornaments that are presently in storage.  Tree ornaments such as animals, musical instruments, etc. can go nicely onto a flat car, gon, or work caboose.  

There are boxcars with Elvis, the Beatles, etc. that have been produced over the years.  Why not have a couple of these kind of cars in your train.  You could even have a billboard proclaiming:  " Tomorrow .... In Concert ... ELVIS PRESLEY ... on the MAIN STAGE ... at your amusement park!"  The sign will always be current because every day has a tomorrow LOL!  

Have fun with your project!  Keep us updated ... hopefully with photos!