Hi Jay,
there are many ways to post goods receipt, but if you like to do it without any purchase or production order, there is only one way : you need to run MIGO and select 561 this is the most common way. But before to do this, be sure that you have created accounting views with mm01 for the material you want to enter stock . To do this you have to activate material ledger for the assigned company code. Also open the period with mmpv.
Cheers,
Sarhan.