You can go here https://outerzone.co.uk/index.asp or https://aerofred.com/ and there are plenty of plans and cad files to choose from. For kits SIG is a good choice there are not as many kit makers as there used to be. You can also try eBay for kits that people are willing to part with. I would suggest a trainer with a flat bottom airfoil first it will be a bit more forgiving.