If you are long term in one RV park, you may be able to get cable tv and internet (or DSL internet) at your site. That is often the best performance and price overall.
We have some good articles in the RVforum Library describing internet and tv options "on the road".
http://www.rvforum.net/miscfiles/Internet_Access_on_the_Road-Rev02_RVF_.pdf
http://www.rvforum.net/joomla/index.php?option=com_content&view=article&id=28:internet-access-for-the-rver&catid=14:newcomers-need-to-know&Itemid=45
http://www.rvforum.net/miscfiles/TV_Service_on_the_Road-Rev3_RVF_.pdf