Sorry, am I being geeky ?
OK, in English - I don't know of any packages which read Microsoft's Publisher format on the Mac. It is typically Mircrosoft proprietary.
However, you can force your Mac to run just about any Windows package by turning it into a 'virtual Windows PC' by using Virtual PC . You install it and then you could install Publisher (and just about any other Windows app) on your Mac !!!
That might be the easiest way to go.
If you want to attempt to import / export files though...
'pdfs' stands for Portable Document Format. You will have seen it all over the Web. Instead of sending each other Word / Excel / Print proofs etc. which can be difficult for different computer users to read, Adobe invented this format for easy document interchange.
I suggested someone on a PC with Publisher output the file as a pdf instead of a Publisher format file. You then take that pdf and open it on your Mac within an app that lets you read / edit / write pdfs. Adobe makes programs that do this sort of thing here .
In a similar vein, someone on a PC with Publisher could output postscript files. These are what printers use to describe digital documents. You then find something for your map (from Adobe perhaps) that reads these postscript files.
Both these options could easily spoil the document flow / layout, but if you're lucky it'll work (not very scientific, hey).
Maybe the best thing is to tell the client they should author their annual report or newsletter in a better / more flexible package ???? Page Maker / Quark Express / even Pages in iWork ????
HTH and was understandable.