Check out http://www.cpcwiki.eu/forum/ and https://github.com/Octoate/cpc-sdcc-rom for some good starting points.
Amstrads can still be had on eBay for reasonable money, and one can gradually buy enough hardware to make a fun system. I just obtained a floppy drive interface that I plan to use to connect an SD-card floppy simulator to my 464 ... fun times :)