What's worse, many of these sites actually want you to pay for this crap, which is insulting, if you ask me. The good hentai sites are in Japan, and are maintained by actual hentai artists, to promote their work. They're all free. There are hentai fan artists in the US with good sites, as well as good hentai collection sites. Since the good sites are maintained by amateur Japanese artists, you can forget about seeing the sites in English.
Most artists know very little English, if any at all.
What English you do see will often be laughably bad. Some artists maintain a separate English page, but this page is often not updated as regularly as the Japanese side. Get a program like NJStar 's NJWin to allow your browser to display the Japanese characters. If the links are titled in Japanese, pass your cursor over each link and look at the status line of your browser. Often the actual URL will be named in English.