"Would this info be in Box 17 of W2?"
The California credit for tax paid to another state is based on the calculated tax due to the other state, which may or may not (and probably won't) match the withheld tax amount in Box 17 of your W-2.
If you complete the non-resident OH state return before you do your home state CA return, the program should enter the correct amount for you.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
