You should be able to find road shoes for under $100. Do you have a Performance Bike or an REI nearby? Both have road shoes at lower prices.

Generally you will see two types of shoes -- ones that allow for a recessed cleat like the two-bolt SPD cleat, or dedicated road bike shoes that leave the cleat exposed. The benefit of the first is that you can walk a lot more easily off the bike in your shoes. You can also find sandals or more casual shoes that use this type of cleat. The benefit of the dedicated road bike shoe is that it provides a bigger interface between shoe and pedal and is purportedly better for power transfer.

A road shoe will generally take multiple types of cleats. There is the Look system, the Speedplay system (a lot of people on the forum seem to like these a lot -- the pedals are two-sided and some find them easier to clip into) and the Shimano SL system (among others). Your bike shop might let you try clipping in and out with different The pedals typically come with a pair of cleats to attach to your shoes, and can range from $40 for SPD pedals to upwards of $200 for the higher end of dedicated road bike pedals.

Hope this helps ...