My sister works part time in a mineral suppliers and two days on normal market stalls. She makes and sells her own jewellery and has built up a good business doing that and it is more regular than craft fairs.As she is in a regular market folk know she is there every week and now ask her to make custom jewellery.They are hard hours though and has to have a large amount of stock and a large van!
Tourist Information places usually have a whats on list for the year, they do up here anyway. Good luck, it was hard for my sister to take the plunge but she now loves market life (especially on a Thursday when she does the indoor market!)