>>419597Just general how to sew videos on youtube should do in the beginning. If you do start a project at some point you should also check out /diy/ and you could be lucky on /cgl/ for specific questions about sewing. /out/ would be better for choice of materials and critique of placement of buttons/pockets, etc.
Get a used sewing machine for $20-30. Anything electronic with an all metal construction (doesn't matter if the outside is a plastic cover, just the structural parts inside should be metal) is fine. You don't need fancy stitch patterns, just straight and zigzag will do. I think that applies pretty much to all of them anyway.
A serger/overlock (specific kind of sewing machine which uses several threads and needles at the same time as well as cutting off excess fabric) is used for finishing seams, but it's not really necessary for your first garments and more of a long term investment if you're certain that you will do a shitload of clothes yourself. There might even be some sort of sewing workshop or whatever in your city you can ask to let you use their machine for an hour or so.
Start with repairing things, and simple stuff like a bed blanket cover.
Search for a fabric outlet in your periphery where you can get cheap fabric.
For /out/ related stuff it's quite a bit harder because for /out/ clothes is mostly a matter of choosing the right fabric, and most of your average "old woman fabric stores" don't really carry merino wool, fleece, softshell and hardshell. Nor will you find accessories (is haberdashery the right term in English?) like waterproof zippers, cord-locks, buckles (like you'd find on a backpack) and seam sealing tape (to make seams waterproof).
They mostly have stuff for dresses, gowns, curtains, and everyday clothes.
There is this page
http://www.extremtextil.deand they ship internationally, but it's pretty expensive.
I am pretty lucky because my local fabric store has a plethora of fleece and softshell for as cheap as 3€ per meter.