Are they still any good? Also how much do i use per jar?
Rennis
It depends on how the prints have been stored. If stored in cool, dry, dark conditions, they can be good for decades.
You will have to try and see if they are still viable. if you are going to prepare syringes, use a portion of 1x1 cm (http://www.google.at/search?q=cm+in+inch) of the spores per syringe. Let the syringe soak for 1 day before inoculation. One of the best directions for syringe preparation is the Psilocyber's Syringe Tek (http://www.shroomery.org/index/par/7967).