I did some research on PDF output tools looking for something simple that would allow me to write html output (from PHP) and have it converted to a PDF.  I eventually decided to use HTML2PDF but this is another alternative. A link to the site is provided below. The things I like about it:

• It's open source.
   
• It has built-in html conversion.
   
• It requires virtually no setup and no external modules.
   
• It's pretty simple to use and works reasonably well.
   

Writing text output with html formatting works well. Writing out HTML tables is a bit tricky and will probably require a customized module tuned specifically to what TCPDF will accept. It isn't nearly as forgiving as writing html to a browser. It seems to need closing </td> and </tr> commands. Column sizing seems to work according to TCPDF's default width unless you specify a width on every column. A background color for a row is only applied to the first cell. It doesn't seem to allow font (face/family) changes. I don't think that it supports .css files.

Despite these limitations, it's a good free PDF program (but not quite as good overall as HTML2PDF). It has lots of capabilities that I didn't spend any time on but may be of value to others. It comes with a whole series of demo modules. 

You can find it at:

http://www.tecnick.com/public/code/cp_dpage.php?aiocp_dp=tcpdf