Is there an inexpensive way to get started with GAL (Generic Array Logic) chips?
I'm not even sure GALs are still around today. CPLDs and FPGAs are preferred I believe, though I'm no expert.  You can dig up development kits from digilentinc.com.  There's a CPLD kit for $18 and the USB JTAG programming cable is $50.  Those parts are Digilent C-Mod and JTAG-USB Cable.  I believe the software (at least starter software) is free.  Good luck!