http://www.freewht.com/
If you scroll down to offers, you will find quite a few people offering free webspace (picture hosting, ad free hosting, and ad hosting). Most of the ad free packages are not really free. They are "accumulate x number of posts at our forums and get free hosting". Some are actually free. Others are promotions (limited number offered), and they usually get claimed within a few minutes.
A word of caution. Most web hosts there have JUST started, and many are only around for a few months before they either go under or sell to another hosting company (then comes changes in packages, pricing, etc...). It's best to stick with a hosting company that didn't just sprout up, since they generally aren't organized or experienced. Most totally free accounts will have a limit (3 months, 6 months, year, etc...)- because they are simply trying to draw you in.
If you try googling, I recommend including in the search the topic that your site is going to be. There are many many sites out there that are willing to host free sites that meet certain criteria.
Good luck!