Someone needs to be the personal representative, which is court-appointed, the executor of a will, or anyone in possession of the decedent's property (the latter I would assume applies to you).
You can simply prepare the Form 56 and mail it in and then apply for an EIN online for the estate.
https://www.irs.gov/pub/irs-pdf/f56.pdf
I believe only TurboTax Business supports Form 56.
