Bead backing: Sova Enterprises sells a bead backing indistinguishable (to me) from Lacy's Stiff Stuff and at a much better price. Purchase by the yard and it's a real bargain. This material holds its shape, won't pill or fray, can be dyed or coloured and you can bead right up to the edge. US supplier - ships by economy surface mail so you'll wait about 4 weeks for the order.
Thread: Buy Nymo in a rainbow of colours. Sold mostly in B (the average beading weight) to D (slightly heavier) or in 00 or 0 for the tiniest beads. Superlon is the brand in your kits - AA is very fine and D is heavier. Carried in black and white - or packages of colour groups, it is more expensive than Nymo but the folks at BeadFX say it's as strong as PowerPro. BeadFX carries both, and they carry upholstery thread for working with heavier stones, knitting or beaded crochet.
C-Lon is also an excellent beading thread. Very sturdy and very little stretch. It's the personal choice of That Bead Lady and it's what she carries, in size D, in a good range of colours. Both are Canadian suppliers.
Helpful odds and ends: It's a good idea to pick up Thread Heaven, a silicon thread conditioner. It's tiny but lasts nearly forever. It reduces static & tangling and strengthens thread. Thread Cutter Pendants are handy too. Both at BeadFX (link above).
Bracelet Blanks: Bracelet blanks come in brass and aluminium, in 1" to 2&7/8 inch widths. Fantasy Beading also carries necklace bases & other blanks that can be used to mount beadwork on backing. All are very inexpensive. Check "supplies" on their site. U.S. supplier, and the order will take a few weeks to arrive.
Ultrasuede: I use Linda's Ultrasuede. She sells Ultrasuede, Ultrasuede light (what we're using for our cuffs in class) and UltraLeather. A metre costs $99.99, but she sells in pieces, too: 6 x9 and 9 x12, 6 x 45, 6x 48, 6 x58 inches. She offers scraps - and lists the average size. She's a Canadian supplier and shipping time seems to vary - but it gets there. Look at her swatch sets for a very nice range of colours.
Denver Fabrics carries a HUGE range of fabrics online, and a big selection of Ultrasuede. Ultrasuede sells as low as $47.00 a yard (US dollars), but you must buy a full yard. On the site, go to "apparel" fabric, then "ultrasuede" (links on the left), to actually GET to the shopping area next, click on the word "ultrasuede light" on the top center banner. It's on the brown strip underneath the words "Ultrasuede Fabric." (Who designed this page??!) There is no minimum order (other than the fact they won't sell less than a yard of fabric.) Their shipping charges for Canada are not listed and you might want to inquire. Sometimes shipping can nearly equal the order price.
Beads, crystals, firepolished beads, shapes (flowers, leaves, drops etc.) findings and all the stuff we love to run our fingers through: See the links at the right for BeadFX (CA), Harlequin (US), WhimBeads (US), That Bead Lady (CA) and Fire Mountain Gems (US).