A really good source is the Romany&Traveler site: rtfhs.org.uk: there are lots of articles you can read. There's one about what to look for in censuses and old records to identify if your ancestors were in the Romany community. Like occupation, family names, children's names, where they were living, who their neighbors were. I would add having DNA matches to people currently in the Romany community. My ancestor WIlliam Riley 1st shows up at his 1st marriage, he is a shoemaker. His 2nd wife Elizabeth, my ancestor, her son Henry worked in the mines as a "Puldler'. One of his grandchildren was named Cinderella. He sometimes had young men with the surnames Price and Stanley boarding with them.