Help me find the right crochet thread in southern Ontario

I know what you are talking about, and I don't think cotton will cut it. The Sak purses seem to be all synthetic fibers. On one hand, I can't recall ever finding something like that in a craft or yarn store; on the other hand, I've never really looked for it, either. Seconding the notion to take the purse to your local yarn store(s); the people there will probably know if anyone makes a yarn like that, even if they don't carry it, and be able to tell you where to find it. Our yarn store workers here have encyclopedic knowledge of every yarn ever made. Good luck!

I think you're looking for nylon cord. You may find the cord you're looking for at Michaels or another craft store, but in the beading/jewelry section rather than the wool/yarn section. Another option is going to sports stores like MEC or a hardware store like Canadian Tire, and looking at their ropes/cords... they may have something thin enough. Good luck finding a color you like.

The Sak bags you linked to are made of polypropylene. I have the vaguest memory of handling a similar bag, and if I'm remembering it correctly, you might check the hardware store for http://www.homedepot.com/p/Everbilt-18-x-425-ft-Gold-Twisted-Polypropylene-Mason-Twine-73226/206094353. The nylon crochet cord seems close but too thin. Try searching for plain polypropylene or nylon cord/twine in the http://www.seamar.com/images/rope/twineSizeChart.pdf.

I want to say mine is nylon or polypropene but that's a hazy memory at this point, so the guesses in that direction are probably closest. Thanks for the suggestions so far.

Almost all the Sak bags I've seen are polypropylene, FWIW. I've worked with http://www.redheart.com/crochet-thread/red-heart-crochet-nylon-size-18 (the same as the Coats one you linked; they're the same company) before. It feels similar to and works at a similar gauge to the polypropylene that the Sak bags use, but it doesn't come in nearly enough colors. Check its Ravelry project photos to see some bags made with it. From the Ravelry project photos for the Red Heart Sizzle, it's much finer than the Crochet Nylon (more like traditional crochet thread), so I'm not sure how useful it would be for bags (unless you were doing things like working with thicker and thinner threads held together.) Hardware stores can be useful for twine in nylon and polypropylene, but they tend not to have a great color selection and the skeins are small, so it ends up being expensive to buy enough for a project IME. Unfortunately, I think if you want more color options than the hardware stores have for this kind of yarn it requires ordering from China rather than Canada or the US. Kind of like how even the largest fabric stores don't have the variety of fabrics available at clothing stores. Working with the nylon or polypropylene you're probably going to want to use for bags like this (it's very sturdy and works well for bags) is not as easy as working with wool or acrylic. It's slippery, doesn't have much give, and is hard on the hands. It does give very professional-looking results, as long as you make sure to leave very long tails when you're starting/finishing/joining a skein (the ends tend to wiggle out, so you'll need more length to weave in than usual.) I think it's possible to melt the ends together when you're joining, but I haven't been brave enough to try that! Cotton can be easier to work with, but it's going to show wear more easily. If you go with cotton, for most bags I'd suggest making sure you use (more expensive) mercerized cotton rather than rougher dishcloth cotton (it'll look less rustic) and carrying the cotton along with some nylon thread or something with less give (cotton tends to stretch, making your bag less fabulous.) Using pre-made bag handles (you can get these at a lot of craft stores) eliminates the worst place for stretching, the strap. Sewing in a lining will also help a lot with making the bag look nice and hold its shape. Anyway, you can get really good results with crocheted bags like this -- remember that the Sak bags are just as handmade as the one you'll be making, since there's no machine that can crochet more than simple edgings. Crocheted fabric is mostly beyond the capabilities of robots at this point. One benefit of nylon/polypropylene for an early project like this is that it's not going to show if you have to rip out stitches (frog them) and rework them over and over again. Good luck!