by Bartimaeus » Thu Feb 21, 2019 12:57 pm
Boards from Oshpark are good quality, and you can order a small number without it being crazy expensive. For more than 10 boards though I really recommend Elecrow.
Both require you to have layer files for your board. Learning Kicad is a good way to do this. It's free software, and it's more than competent enough to do multi-layer boards, let alone single side.