Where Will I Host My Files?
Good question, where indeed. Somewhere that is extremely reliable is a good starting point, as intermittent downtime for your MP3s can cause no end of problems.
If you are planning to list your podcast on other websites, most will not want to actually host it for you and certainly not for free. Instead, they will just require a link or an RSS feed.
If you are able to find yourself some free webspace, or if you have your own website, it will make perfect sense to host it yourself. However, do make sure that your web hosting package allows you to do this, and that it will be able to cope with your growing audience and constant downloads!
If things really begin to take off and your podcast listeners start to cause you bandwidth problems, then you really should only see this as a good thing and upgrade your hosting package accordingly, to meet your demands.