If you'd like to do other languages, websites like moviesubtitles.org have many versions. My guess is this site and the ones like it pull down torrent and usenet feeds and pull out the .srt and other subtitle files and then add them to the library. So there are problems periodically. Once a good set is found, the problem will be adjusting the timing, but as the subs are mostly sourced from retail, they are accurate, when a good set is found.

Even if we don't know the language, having multiple .srts with similar timing structures will let you know where to time them out, and can use google translate to get an approximation of what's being said to know where to place the sub.

What program are you using to do the subs? I had considered something similar but on the Mac, DVDStudioPro doesn't allow you to move multiple subs at once, major problem. Also finding a program which allows you to import different flavors/formats of subtitle files is also important.