Asset Valuation in Balance sheet


I cannot find a good approach to manage assets in the balance sheet.
The depreciation is quite easy but what is the best way to book the asset value to the GL?

If I create an existing asset its value does not show up in the balance sheet. I read somwhere that you need to post the GL movement separately. But what is the value added of this? Why the asset creation does not post the asset value to the balanace sheet directly?

Is there a good tutorial/documentation out there that explain how to deal with assets?