Batch convert TIFF images to PDF?

You can try ImageMagick. I'm trying this on Linux, but it's available for Windows as well. I just have to type: convert example.tiff example.pdf and I get a PDF. With just a little batch magic, you should be able to easily convert a directory of tiff files to pdf.

Or, if you need all tiffs in the same PDF, you can do convert example1.tiff example2.tiff example.pdf.

The tiff2pdf mentioned in Bobby's answer is probably part of libtiff, and you can get Windows binaries through the GnuWin32 project. The Cygwin environment probably includes a libtiff package as well, though I haven't verified. Both Cygwin and GnuWin32 versions are free software.

Davince Tools (sic) includes a scriptable commandline tiff2pdf utility for Windows. This is a shareware toolkit.

Dreamsys Software also provides a Tiff-to-PDF converter (download). This appears free to use.

Using ImageMagick as follows should also work:

convert ^
   c:\your\current\directory\*.tif ^
   c:\your\output\directory\allimagestogether.pdf