My calculator works fine but dried up - probably needs new ink..... How and where can I get it?

In dries out, try purchasing new ink cartridge it will probably work just fine.

The machine you have uses a pressure sensitive paper which is available at Staples, Office Depot or Amazon.com

If the ribbon is fabric, you have to get a replacement. As for paper check several suppliers if you want to buy quantity otherwise a roll will do.

I think this is what you are looking for.
http://www.aroundtheoffice.com/XL-121/products/4461/

You need a new ink cartridge. You should be able to get one at most office supply stores.

Look at the rubber numbers inside the machine. They are probably clogged with ink (at least mine was). I researched and could not find a specific answer, finally I asked how to remove ink from your hands. Everyone said use bleach. I tried clorax 2 bleach on the rubber numbers wiped it clean and let it air dry. Worked like a charm!!! This might not be the proper way but it's working.

It's not a ribbon, but a little ink roller that is under the little window by the printer digits. Mine is dry, and I need a new ink roll or a way to re-ink the old roll. Sorry I'm not much help.

It is probably clogged. You need to using lint free swabs and vinigar to clean it. The vinigar disolves deposits of dried ink.

If this doesn't work then it can be a print head problem and that is usally cheaper to replace the printer than it is to repair it.

Try www.fjaproducts.com Nu-Kote NR-78BR ink rollers - worked for me!

Unless the ink roller that you installed was dried out, usually, the replacement rollers just snap in place and are good to go. Check to make sure there is ink on the roller by either pulling the ink roller out again, and touching it with your finger. If no ink on your finger, you might have received a dried out replacement roller. Also the roller should be somewhat like a sponge. If you push against the sponge and it doesnt spring back and it stays indented, then the roller might also be bad. If you happen to have a bottle of ink for an ink pad, you can try soaking the roller with the ink so the roller is wet, (but not DRIPPING WET) and try it again in the calculator. IF you get some image for a little while, then I would say try a new fresh ink roller.
Hope this helps.