Sounds like someone has a can of bolts sitting there and doesnt remember where they all went. Thats why its always recommended (and so important) to bag up everything, label it and have it in one place as you disassemble....
I highly doubt there is a "bolt diagram" anywhere. Best bet is to post pictures of what you've got questions of and someone will probably know what they are and where they go. As for missing bolts, maybe one of the guys parting an engine has them, or you may just have to buy another set at the dealer.