I'd recommend looking at the BLS as a starting point.

Robert Half has several guides that are free for various industries.

A lot of larger universities post all their salary ranges publicly for most of their entry-level positions.

Some employers post ranges in their job postings.

Good luck,

Dave

I would also reach out to your local chamber and see what data they have that they can lend you. 

You can find entry-level comp data at Ohio Means Jobs, apply your applicant information and of course, tap local resources (i.e. Employers Resource Group).