Just bought 2002 Saturn SL2. Immediately manual

if it is a cable clutch ,replace the cable as it is not allowing the clutch to engage
If it is hydraulic operation , replace the clutch master cylinder

You need to adjust the clutch cable. It runs from the fire wall to the shift lever on the back of the transmission.

I think you need to call around to junkyards and find a used transmission to fit your car. You can find sites by googling it as well. Most likely any saturn manual transmission 91-98 will fit, possibly even up to 2002 if you stay with the S series cars. They have an interchange which will tell you.
Take this time to replace the clutch too. The big caveat here is that the DOHC cars SL2 SW2 SC2, transmissions have a different final gear ratio than the SOHC cars Sl1, SC1 SW1 so you have to know which type you have and get one from a donor vehicle which is the same.

Ask at a wrecking yard, these guys know about interchange ability

Time to find a much lower mileage used tranny and have it put in. Replace the clutch components with new stuff while you are at it.Note that the transmissions 91-99 will most likely swap but you must know whether you have an SL1 or SL2 and the donor car must be the same..

Your valve body and possibly input shaft nut need to be replaced. The valve body's booster valve is worn down and won't create pressure. Before it went completely out it slammed on the input shaft nut and loosened it.

You need to replace the valve body and retorque the input shaft nut. The transmission is not junk. The above needs to be replaced and change the filter and fluid and do it every 20K miles.

sounds like a fuel pump check fuel pressure but it could b alot of things spark fuel compression timing check basics first

I had this same problem with my 1998 SL2 after about 170,000 miles. There is a plastic bushing at the end of the shifter cable that holds the cable to the shifter - it probably broke. Remove the center console inside the car to access the bottom of the shifter. I checked my local Saturn dealer to find the replacement cables (come as a set) are more than $200. So I went to Lowes and bought a beam clamp and a large washer to hold the cable to the shifter. It has been working fine for more than 28,000 miles and cost less than $3

yes take it back if you are still under warranty.

Check the Transmision kick down cable,,which is attatched to the throttle cable and goes into the transmission,,it may need adjustment.