In days of yore, I made a lot of my own outdoor gear: sleeping bags, parkas, down jackets, tents, gaiters, wind pants, yadda, yadda, yadda. And, if you have more time than money, you can do OK on simple things or using kits (does Frostline still function?). But, the sad fact is that the slave labor wages in the Far East combined with the economy of scale of manufacturing make many outdoor garments and gear for sale on the market
cheaper than the cost of materials at retail to make them yourself. Yeah, I know, makes me sick, too. That's not a reason to avoid making your own stuff, but it may put you off.
This lady has a wealth of good advice and a superb collection of links if you are going to pursue this:
http://www.specialtyoutdoors.com/
As to sewing machines, any decent home machine will probably suffice. I used a Singer vintage 1970 for a lot of my sewing, and now own a Husqvarna which is tougher and better ... but Husky's are expensive. An older, used Singer, if reconditioned, might be your best bet. Emphasis:
older Singer. My longtime paddling partner was in the repair biz for 15 years, and he quit selling Singers about 1993. The name was there, but the quality of previous years was not.
One item which is worth making is your own dry bags, custom tailored to fit your own gear (especially items which are odd sizes: Thermarest pads, tents, tripods, etc.). These are most easily fabricated using heat-sealable nylon from Seattle Fabrics (or similar). Chuck Holst has published a detailed how-to article on this, which I used to make bags for my VHF's, for example. The sewing is simple, and a home iron will do a bang-up job on the sealing.
If someone is interested, I will search around for Chuck's article.