For the Mac you should just have to get an Airport card (Apple's wireless networking cards). Otherwise you would need to install a PCI wireless card like in a PC. For the most part all Macs made in the last couple of years use the same hardware as PCs do. It's no harder to do, and quite often is easier than many PCs when it comes to adding internal hardware.
FTP stands for file transfer protocol, and is what many sites use to transfer files on the internet. This used to be the cheapest way to get older Macs and Windows computers to share files, but I am pretty sure OS X includes software to allow the two to see each other directly. I don't have an OS X computer though, so I can't help too much with that part. As you noted though, it would just be easier at this point to get each one onto the internet.
Good luck and keep us posted.
goates