Info is a specialized format with few formatting capabilities, it's basically man with hyperlinks. Most info files are generated from a Texinfo source with the
makeinfo command. Texinfo is designed to accommodate a wide range of outputs, both hypertext and printed, with basic or pretty formatting. Supported output formats include info, HTML, DVI, PostScript and PDF.
The PDF may already be present in the same package as the info file or in a separate package (depending on how much your distributing).
If it isn't, install a Texinfo setup and get the source of the package. You can then process the Texinfo source with
texi2pdf, and you'll get a manual in PDF format with nicer formatting.