What type of accounts require W9's and W8's?
I have always gotten them for loans, but are they required for deposit accounts accounts as well?

yes -- you might want to check if your using a substitite W-9 as part of your signature cards.

What does a Substitute W9 look like?
Is it a statement saying this is my SSN?

You can review IRS guidelines such as "Instructions for Requestors of W9s" to determine from whom a form should be obtained. Remember, a U.S. person, including a resident alien, signs a W-9 and a non-resident alien signs a W8-BEN.

Thank you all.

Technically, if you are limiting the requirements to account opening situations, a W-8 is only required when opening an interest bearing deposit account and a W-9 is only required when opening an interest bearing deposit account or involving a real estate secured loan transaction.