how do you check the tranny fluid??

hello
i just bought a 97 catera with 45k miles, but the tranny is bad, and i do not know where to check the tranny fluid. if i do need to get a new tranny does anybody know of a good cheap place for one. thanks
NICK

I have a 2000 catera and this car has to have the strangest way to check the level. (1) start the car and have on a rack after it is warmed up totally. Have in drive I suggest the brake on (someone inside) (2) Unscrew the fill plug on the side of the transmission and look for it be bearly overflowing the fill hole. A lot of the new cars with automatic trans do not have a way to check the level or fill it normally. It might seem stange but I watched them do it in the shop when it was flushed. In Arizona they suggest you flush it every year.