The only ete to pdf conversion that makes sense would be the export of reports from Exam Test Engine test files (.ete) to a PDF document file.
To convert ete to pdf this way, simply download and register Exam Test Engine (it's free), load up your .ete file and use the print report function to generate a PDF version of the report via virtual PDF printer. If you do not see virtual PDF printer (just physical printers or Windows XPS), you will have to install it first.
You can also find plenty of website that offer this for cash, but it should be doable for free.