What's the salary for doctor office RNs ?

I'm a new graduate RN & I'm going for an interview at a doctor's office. I know salary is negotiable, but don't have any idea what the average is for a doctor's office. Also, do you usually get medical benefits working in a doctor's office full time ? I was making $18.00/HR per diem as a Nursing Assistant while going thru nursing school...so don't really want to go lower than that..is that realistic ? I do have 15 years experience in the business world and was an administrative assistant in the past. I need the RN experience...since it's so hard finding new grad nursing positions...
Any advice would be greatly appreciated.
Thanks !!!