I disagree with the comments that having an ebook reader requires a Windows computer, but I will say that you need to be careful of the ebook products you choose.
I do have both a Windows machine and my Macs. I don't put personal information on the windows box as it is my gaming machine, so it is online with a lot of software that I cannot trust. For years I have used macs for all of my ebook tasks:
- eReader: purchasing, reading, converting and file transfers.
- iSilo: converting and file transfers.
- eBookwise: purchasing, converting and file transfers.
I even managed my Sony Reader on my mac, for the few months I had it.
Having said that, I specifically chose products that had tools available for my mac. The Kindle, with on-unit shopping, direct dowdloads, and online conversions would seem to do a great job of removing the dependence on a specific desktop platform. I would reiterate the earlier suggestions that you try the perl scripts, Calibre or Amazon's email conversion.
If you are able to extract the text, don't be afraid of a two-step process. You may not be able to go directly to Kindle format, but you may be able to get the data into a format that the online Kindle conversion can easily handle. It is not as convenient, but it sounds like this is a bit of a one-off, so it may be a small matter in the long run.
Good luck, and let us know how it works out.
Jack