There are some good free books on VHDL on the internets.
If you just want to control something (like your garage door) at home the Arduino is cheaper and easier. If you want to get serious about precision control of that something then go FPGA. I have a Altera kit at home that I have been playing on to switch leds but it is just so I can learn VHDL. I am going to use FPGA's in future so I need it for work. For home I would stick with arduino and C the FPGA is complicated and usually also a BGA package which just complicates things further - unnecesarry complications. Added to that possibly multiple powersupply voltages and offboard flash to boot the fpga at start up...




