After gathering together all of the parts needed, I was finally able to run some homebrew on my Wii today.
I don't have a Gamecube memory to SD converter, however, I have an Action Replay GC kit which comes with a GC Disc and a GC Memory card and a Max Drive which also comes with a GC disc and a memory card with a usb port for connecting to PC.
I loaded the GCOS files onto the Max Drive Pro through their pc software, and plugged it into the Wii's Game Cube Memory Slot A, I put the Action Replay into the Wii's GC Memory Slot B, I loaded the Action Replay Disc from the Wii main menu, went to freeloader, ejected the AR disc, and inserted the Max Drive Disc and Max Drive Boots (Wierd because I could not boot this disc from the Wii menu)
So now from the MaxDrive disc I can run .dol files on the Wii.
So far I have loaded GCOS and gone through the menus but nothing really works. What's next? I never had a gamecube, what other Gamecube things should I try?
If any of the developers of this GC software want me to help you test some code, let me know.
UPDATE: More info has been posted by Sappharad over on the GC-Dev forums:
Just tested my AR on the Wii. It's the first version, 1.06... And it works!
SDload is running on my Wii as I type this. So that's some good news.
I'll do a bit of drive experiments later to see if I can get a firmware dump for the GCLinux folks. Nothing strange happens when you try to unlock the drive and read the firmware the old way, but I haven't actually displayed any output at this point. I need to learn how to write files to SD cards, since there is no BBA this time.
It appears that using the old method of enabling drive debug to do a firmware dump returns all 0's.
Oh well. It was worth a shot. (There's still a chance I messed up, but I was working off of old code that I know was working.)
For the record, and in case anyone wants to know, Virtual Console titles are encrypted. It appears each game you download also has the emulator for it attached, with seems like a waste of space IMO. Sonic 1, whose original rom was 512KB, is a bit over 2MB on Virtual Console. (Oh, and for genesis games you CAN play them with the Wii remote, in addition to the classic or GC controllers)
Had a chance to compare Virtual Console data with someone else's yesterday. The same executable is over 95% different saved onto two different Wii's. Exact same size, just encrypted with a different key as expected. It doesn't seem like it will be easy for us to "create" our own channels in the near future. This is where I stop for now, as I lack the time or resources to try anything more elaborate.