I built my SBC without any prior experience. You pretty much just have to connect all the adress and data lines, and then figure out the chip selection logic. I used an MC68B50 for the UART, which can still be found very cheaply on eBay.
Might as well build a Z80 system while I'm at it. And Zilog's UARTs are quite nice, or so I've heard.
I went with a 12V-EEPROM at the time, so I had to write my own emulator to speed up my development cycles :)