The Quicknet 2000 has a BNC connector (not like a TV aerial connector when you're an RF engineer :-P) and an AUI connector (15 way D-range)
As mentioned you can use the BNC connector to connect to anything else which supports a 10 base 2 connection, or an AUI to 10 base T (RJ45) converter which are often easier and cheaper to get hold of than 10 base 2 to 10 base T adaptors.
You might need to modify the QN2000 card depending on the AUI adaptor, from memory some adaptors require ground on a certain pin which is open on the QN2000.
Also, I think it needed a fuse holder fitted or something trivial, as the adaptor requires power from the AUI port.
Miami(DX) supports the board through the z2-mb86950.mni device driver.
I also have a copy of quicknet.device somewhere if you prefer to do it that way, which would also allow support through AmiTCP/Genesis, in theory.