Here are a few good options you should never overlook when trying to get something for nothing in the sewing world.
Swaps: As showcased by the many excellent meetups and virtual events that take place, there's great opportunity to pocket a lot of free stuff at a pattern and fabric swap. Particularly if you're feeling greedy. Remember that whatever you want, someone probably already has and is looking to get rid of.
Giveaways: the sewing blogosphere wouldn't be complete without giveaways. Sponsored, anniversaries, frivolous, just because, competitions and random draws. Enter whatever takes your fancy and you might just get a bundle of free stuff!
Gifts: Of course, an easy one here. Use any sort of gift occasion to justify that fancy Nani Iro double gauze.
Swaps: Not so much a freebie but still sensible. Seen something you like? Work out a way to swap until you get it!
Network (friends, family, co-workers...): Here you guys will need to get a little sneaky, a little cheeky. Once people know you sew, you can inherit lots of scrap/spare fabric from friends and family. Relatives and elderly acquaintances may pass their legacy stash on to you, kids may grow out of old clothes, people may lose an awful lot of weight, they may even have spares from their own projects. Ask and ye never know what ye might receive...
Salvage: Peter found it in bins, I liberate from event decorations, you may salvage from theatre, school or costume spares. The possibilities are endless.
Commercial Opportunities for vendors: This counts for bloggers as much as for non-bloggers. Think about sponsors (who can also offer discounts to your readers), think about becoming a pattern tester, think about reviewing books/courses and classes. Think about applying to one of the blogger networks.
Not only is this a good way of having access to new resources, but if you plan to turn your sewing into something more then this is a good stepping stone.
Commercial opportunities for you: Smple. Work out how to make money from sewing. Melissa has mentioned several times how Adsense pays some of her sewing bills, and now she's going even further by releasing her own pattern line. You could just take commissions from friends and family, but it will definitely make things easier on your bank balance too!
Anything I've missed?
Anything I've missed?