new to blogging, trying to figure a pricing point

I currently intern under myself (haha) for an unofficial student blog for people interested in The University of Tennessee-Knoxville. The website is volblogs.com. Take a look and check out our current banner sizes. WE’re moving to all local advertisers in knoxville, and I have no idea where to start on pricing. We’ve been running ads for free while we collect data. Currently we average between 400-500 individual IP addresses a day, and our avg is steadily increasing. I plan on going by a per-impression pay plan, since we’re not really big enough to earn anything off of per-click. tell me what you guys think.
Thanks

See original post by claysk8