If you have a profit motive for your hobby, then you would usually enter the income and expenses in the
Business Income (Schedule C) section.
Business Income: Menu Path:
Income > Business / Rental Income > Business Income (Schedule C)
If it really is a hobby and not a business, you need to enter any hobby income on the
Other Sources of Income screen as hobby income. You won't be able to deduct any
expenses for your hobby.
Hobby Income: Menu Path:
Income > Uncommon Income > Other Income