With looks of that wood and the help you will find here you should do just fine. I say you made a good purchase. Did the guy you bought it from say when it was harvested? I like my osage to cure at least 2 yrs but 3+ is better. If you can knock on it and it sounds somewhat metallic its pretty well cured. If it has a dull muted sound its probabley gonna need to dry out some more. Roughing it out to near bow dimensions will help speed the drying process up a bit. Look forward to seeing what you make of it. Danny