First off, check to make sure there isn't a Mac HPNA card that would be cheaper; see
.
Is there a way to connect Macintosh's with HPNA?
According to this FAQ, Proxim makes devices that work with Mac's but not, alas, OS 10. But, maybe they'll have it soon, or somebody else has it. The ideal thing would be to buy some $30-$40 USB card with Mac drivers, but I don't know if they exist.
If that won't work, or if the Mac cards are too expensive -- Don't know about the Compex, but my theory has always been that the
Netgear PE102 Ethernet to PhoneLine Bridge would do this sort of thing. As I understand it, the bridge basically makes your phone jack the equivalent of an ethernet jack. So, if the MAC would work if it were connected by Ethernet to your network, it would work with the PE102. The cheapest price I've seen on the PE102 is, surprisingly, $100 + shipping direct from
Netgear. However, Staples lists the PE102 for a ridiculously high $184, so if you can get them to do their 110% price match you could save a few bucks. Also, with Staples I think you could return it to a store if it didn't work, which would save you some shipping.
I did do a little reading about the Compex -- I believe it is cheaper ($75) and has more features than the PE102 (it can be either a router or a bridge). The main things that make me leery are that (a) I've never heard of the company -- I think it is just now making somewhat of a presence in the US (b) the reviews said something about it running very hot to the touch, so you had to be careful of it.
Anyway, IF the Mac would work connected to an ethernet jack (and I know nothing about networks with mixed PCs and Macs) then I'm guessing either the Netgear or Compex products would work. But, make sure they are easily returnable if they don't.