The typical asking rate per listing is in the $20's per square foot per year. The Madison region is going through a an increase in rates. In the last 3 months, the median rate rose $1 per sqft per year. That's a 5% rise in rent.
In the last 90 days, 95 listings have been listed, so you'll want to check back regularly for new listings. About 128% of the listings in the Madison are subleases, so you might be able to snag a great spot on a short term. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,100 sqft. Most buildings in this market are approximately 2 floors. Most buildings in this market were built in 1989 and are Class B.