Brandi,

I would just consistantly ride on the part of the road that you feel is safe, however close to the shoulder that may be. If the shoulder is such that you will fall if you go over it- then leave a couple feet between you and the shoulder. You have the right to take up as much of the lane as you need to operate your bike safely. If the driver threatens or harasses you, get the plate and call the police.

It's really helped me to feel safer to have a mirror, though. That way there aren't as many surprises.

Nanci