I think you could find out a lot of the answers to your questions just using search engines and calculators. For example, when you type "ounce gram" into google, you find out that there's 28.3 grams in an ounce. Then, when you type "28.3 x 2.12" into a calculator, you find out that your 2.12 oz package has 60 grams. I'll leave the rest (i.e. searching bluelight for recipes and techniques) to you, as the information is there to be found. As for how they "work", that's due to the traces of morphine, codeine, etc., that's left on the surface of the seeds, though the amount can be highly variable depending on the strain of the flower the seeds came from and the degree to which the seeds were washed before packaging. The high variability in strength is cause for caution if you were to go get larger amounts of seeds.