Sewing is the way forward, but it is time consuming. I don't bother making things out of stretch material. It's harder to sew than woven and since I don't have time to sew everything, I save my sewing time for tailored, woven pieces.
Goldhawk Road in Shepperd's Bush London is a great place to buy fabric. I have made channel style jackets with boucle ordered from Lynton Tweeds in the North of England and you can order proper Harris Tweed from Lewis. These are both easy fabrics to sew and you get real value for your sewing time since jackets and coats are expensive.
There are plenty of patterns around. Finding the right fabric is the tricky bit. I particularly like Burda magazine patterns and Vogue patterns for dresses.
Here is an example of all the patterns you get in a single issue of Burda:
burdastyle.ru/stati/pervyy-anons-burda-5-2017-/