I'm sorry if it seems like we are being rude, but this is a non-simple problem that people get paid a great deal of money to do correctly. Designing a board for a moderately sized FPGA is several steps below the design of a modern PC motherboard, with high end, 3000+ pin FPGAs being several steps above. This is the one point that has kept me away from FPGAs. Who cares if I can design a full processor on an FPGA development board if I cannot possibly transfer the FPGA to my own designs.
This is one area that, for hobbyists, is a case where if you cannot do it yourself, you're not ready.