NTRA has a pretty good stakes calendar that lets you know what races are coming up, where you can watch them, and even gives you various articles and sometimes past performances for them:
http://www.ntra.com/races_index.aspx
Certainly a good way to start following it although getting Dish Network with TVG and HRTV is going to go a long way as well. Both channels are available on the base package and I think it starts as low as $29.99 a month.