How do I record a sold fixed asset in the general ledger?

Before the sale you need to get your depreciation of the asset up-to-date.
This journal entry is:
Debit Depreciation Expense for the amount of depreciation for the asset
Credit Accumulated depreciation for the asset


Debit Cash for the amount received
Debit Accumulated Depreciation for the amount of accumulated depreciation of the asset
Credit the asset account for the cost of the asset that is on the company's books

And the difference between these entries will either be Debited or Credited as a gain or loss on the sale of the asset.