I just bought myself the Garmin Forerunner 305. It's slightly over $100 but you can get used ones for under $100. It combines the speed/distance tracking of the Garmin with a heart rate monitor in the same unit. It's watch-style, but I just strap the watch to my handlebars (over a light mount to make the "wrist" bigger) and it works fine. And you can download the data to your PC.
http://www.amazon.com/gp/product/B00...SIN=B000CSWCQA