There are a number of places that sell replacement needles, cartridges,etc. with charts that will help you identify what you are looking for.
You might want to get in touch with these:
http://www.garage-a-records.com/needle.htmlhttp://www.everythingradio.com/Record_P ... eedles.htmhttp://www.jukemania.com/magnavox.htmhttp://www.needledoctor.com/In most cases, all you have to do is pull up gently on the retaining arm that is positioned over the spindle and move it to the right, then stack a few records on top of the spindle, and then move the arm back over to it's position. It should clamp the records on the spindle. Then, slide or turn the control to the automatic position and turn it on. The first record will drop onto the turntable, and the tone arm will swing over and play it. When it comes to the end of the record, the tone arm will swing back to the right, the second record will drop onto the first one, the tone arm will play that, etc. When the last record is played, the turntable will most likely shut itself off, automatically.
It should operate similar to the Crosley Stack-O-Matic. You can download the PDF instructions from this jump:
www.crosleyradio.com/man/cr89m.pdf