From the map press the first letter of the animal's name and its position will show up. The rhino will usually be in the lower right hand corner if you have a permit.

The animals you can find are as follows:
I: Impala
L: Lion
Z: Zebra
B: Buffalo
W: Wildebeest
R: Rhino
C: Crocdile

Go inside the safari store. Move the mouse into the upper left corner. Press CTRL + 4 to get a free $1000. Now go buy some guns and make some carcasses!