I have recently become the guardian for a 3 year old domestic short hair tabby, I am wondering what shots she should get at her upcoming vet visit? As far as I know, she has gotten all of her prior shots.

If she's up to date on all her shots, why do you think she needs a shot? Do you have any record of prior shots?

Is she an outside cat or does she spend part of her time outdoors?

Just talk to the vet. They will be better able to tell you which shots she may need, and explain why.