Hi Winwood !
We are still looking for someone able to write us a quick SANA-II driver for the ESP8266. It shouldn't be a big job but it requires someone's time. As of today, I can't answer your question on "when" because work on this part hasn't started.
I went online with V500+ with a Plipbox connected on Parallel port. It's actually the easiest way to get online on A500(+). I did it with the Roadshow stack. It was really straight forward. I have to admit it still isn't the best solution as the Plipbox is really slow (40KB/s... versus the 2MB/s we got on A600 with PCMCIA Ethernet and it is a bit unstable...).
Software part for Plipbox :
Where to buy Plipbox "plug'n'play" :