My interest with FPGAs is more designing processors rather than interfacing with electronics. I like the products from OpalKelly [http://www.opalkelly.com/ http

My interest with FPGAs is more designing processors rather than interfacing with electronics. I like the products from OpalKelly [http://www.opalkelly.com/ http://www.opalkelly.com/] for this as they have a USB interface and C libraries on the computer side, HDL on the FPGA side to abstract the host->FPGA communication allowing you to just focus on your design.