Hi Uncle Chris,
Looks like you should first make acquaintanceship with your new beast.
Do download first the owner's and service manuals available on this site: click on "Library", then "Dual", then 1225 and you will get all the info about it.
For the needle, it should be attached to the cartridge which is located under the front of the tone arm (if it is not missing...) Usually, most Duals are fitted with a "Shure" cartridge attached to the head shell holder, which is reachable by pushing backwards the chromed lever at the right of the tone arm: it will fall right in your hand.
The needle fits in the cartridge, and might also be missing...but can be found at various on-line shops (try "Needle doctor" or "Garage-a-Record",etc.)
Do you see a cartridge when you push the lever?
What is written on it?
That's a beginning...
Will gladly help answering further questions...
Dual 1019/Shure M97xE/Jico SAS stylus.
Thorens TD 146 & TD 166/Ortofon OMB5 and OM40 carts.
Marantz Mod 6170/Marantz E 5000 cart.