@lymang,
Yes, Amiga ethernet cards are obscenely expensive compared to PC ones, but you have one other option on the A2000. It has ISA slots which can be accessed via a card called the Golden Gate. The Golden Gate is a rare card itself, but if you can find one at a reasonable price, it will act as a bridge to allow the use of cheap ISA ethernet cards in the A2000.
Just another option I thought I would offer for consideration. I have not personally tried this option but have read of others using it.
