I need to develop a print driver to print from any application into a TIFF file. Does someone know of resources or a good SDK vendor that would enable me to do that? Environment is Windows, any language.
The Microsoft Windows Driver Kit (freely available from the linked Microsoft site) has extensive documentation and examples on writing printer drivers. You can check the online printer driver page of the DDK docs before downloading it.
Edit: One commercial alternative that would probably be much quicker to deploy is VeryPDF's DocumentPrinter. It's rather pricy (currently $1500 for a developer license, $399 for a server license), but from what I've heard their support is rather good so if the price is tenable for you this may be a good option.
There's also a SDK from DirectConvert, but I couldn't find any pricing info and don't know anything about them.
Depending on your usage patterns, another option would be something like TechSmith SnagIt, which has printer capture facilities available. This is not a SDK, though.