96 Infiniti I30 - wont reverse

[Nikki_B]

I have a 1996 Infiniti I30. When I went to drive it today, I noticed that it wasn't "clicking" into reverse. When I shift into the other gears, I can feel it "catch" but not on reverse. It feels really loose...and....my car wont go anywhere in reverse either.
I read something about a transmission selector switch going bad or getting gunk in it could cause this.
Where is this switch located? I bought the car used so I don't have the manual.
Hoping to check all small issues before I freak out about having to buy a new transmission.
Thanks to anyone that can help me with this!!!
~NIkki

[maxhopper]

The shift cable connects to the transmission on the side closest to the radiator. Sounds like the cable may be loose.