This was initially made about 8 years ago but I refresh it up a bit every so often- Links may eventually not work but I will update it every so often.
Please look here before directing questions at me, most can be answered in their database.
http://www.livejournal.com/tools/memories.bml?user=fursuit
Color:
http://www.colormatters.com/colortheory.html
Horns:
https://www.etsy.com/shop/BlackCraneCreations?ref=l2-shopheader-name
https://dreamvision-creations.myshopify.com/
http://www.furaffinity.net/user/starborneworks
Fur:
https://www.aliexpress.com/store/group/fur/1418159_259985894.html?spm=2114.12010615.0.0.3d2d256annnrGk
https://hairymannscloset.com/
http://www.distinctivefabric.com
http://www.fabricempire.com/
https://furaddictionstore.com/collections/faux-furs
http://www.imstuffedfur.com
http://www.crscraft.com
http://www.nftech.com
http://www.fabric.com
http://www.syfabrics.com
http://www.montereymills.com
http://www.mendels.com
http://thefabricexchange.com/
https://www.mohairbearmakingsupplies.co.uk/fabric-room/faux-fur-fabrics
https://fursuitsupplies.com/index.php?route=product/category&path=35
Foam:
http://www.thefoamfactory.com/
Hobby Lobby
Joann Fabrics
Here are some people that sell supplies for making suits: (I did this off the top of my head don't be offended if you aren't on here.)
http://www.furaffinity.net/user/drakonicknight
http://www.furaffinity.net/user/keeatah
http://www.furaffinity.net/user/phazonalloy
http://www.furaffinity.net/user/artslave
http://www.furaffinity.net/user/crystumes
http://www.furaffinity.net/user/head-spyn
http://www.furaffinity.net/user/starborneworks
https://dreamvision-creations.myshopify.com/
https://fursuitsupplies.com/index.php?route=common/home
http://www.roofur.com/store/
Absolutely amazing wings:
http://www.etsy.com/shop/BionicConcepts
http://sunnybrook1.deviantart.com/art/Realistic-Wing-Tutorial-P-1-175022078
http://sunnybrook1.deviantart.com/art/Realistic-Wing-Tutorial-P-2-175523669
http://sunnybrook1.deviantart.com/art/Realistic-Wing-Tutorial-P-3-176221360
http://sunnybrook1.deviantart.com/art/Realistic-Wing-Tutorial-P-4-181122223
http://sunnybrook1.deviantart.com/art/Realistic-Wing-Tutorial-P-5-194567747
Cosplay supplies: (Also wonderflex here)
http://www.cosplaysupplies.com
Armour making:
http://www.therpf.com/
http://amethyst-angel.com/armormaking.html
http://www.entropyhouse.com/penwiper/costumes/helmsdeep.html
http://www.youtube.com/user/AweMeChannel/videos
https://www.kamuicosplay.com/
Duct tape:
http://www.intertapepolymer.com/Pages/default.aspx
http://www.tapebrothers.com/
http://www.bettymills.com/shop/product/view/Intertape%20Polymer%20Group/IPG761-78750.html
Taxidermy eyes, noses, and teeth:
http://www.vandykestaxidermy.com/
http://www.tohickonglasseyes.com/
Eyes:
http://community.livejournal.com/fursuit/3209117.html
http://beetlecat.livejournal.com/2919.html
http://community.livejournal.com/fursuit/2281486.html
http://www.usplastic.com/catalog/item.aspx?itemid=23376&clickid=redirect
http://www.tapplastics.com/product/plastics/plastic_rods_tubes_shapes/acrylic_cabochons/139
http://www.delviesplastics.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=DPI&Category_Code=Acrylic_Balls_and_Cubes
https://www.verycharms.com/products/crystal-glass-magnifying-high-dome-half-sphere-round-cabochon-8mm-10mm-12mm-14mm-15mm-16mm-18mm-20mm-25mm-30mm-40mm-50mm?utm_medium=cpc&utm_source=googlepla&gclid=CjwKCAiAhfzSBRBTEiwAN-ysWPittoBqFn3Q_58zc5h6CZFVttykB7TkofZGlyREnojCIogGFmTzjBoCN1YQAvD_BwE&variant=46016345094
Plastic sheets:
http://www.tapplastics.com/
EL wire:
http://www.coolight.com/Techno-Flash-EL-Wire-p/tflash.htm
http://www.bewild.com/newpoeleledl.html
LED's:
http://herestohaunting.ecrater.com/
https://www.adafruit.com/
https://www.sparkfun.com/
Glue sticks and glue guns:
http://www.glu-stix.com/
https://www.hotmelt.com/
http://www.amazon.com/Surebonder-725R510-10-Inch-General-Temperature/dp/B001FWXXII/ref=sr_1_4?ie=UTF8&s=home-garden&qid=1295895322&sr=8-4
Duct tape dummy tutorials:
http://www.sunnyvalleyc.com/dtd-tutorial
http://www.citymuttfursuits.com/dtd-tutorial/
http://www.beetlecatoriginals.com/dtd/
http://www.madefuryou.com/how-to-order/duct-tape-dummy/
Silicone paw pad tutorial:
http://www.furaffinity.net/view/5251778/
Some very well laid out pictures and explanations of suit making:
http://fursuit.tanidareal.com/
Resin mask mold tutorial:
http://qarrezel.deviantart.com/gallery/#/d1p7axf
Resin/Silicone supplier:
http://www.smooth-on.com/
https://www.reynoldsam.com
Stretch fur tutorial:
http://fursuit.livejournal.com/4065775.html
Dog collars:
http://www.3dirtydawgz.com/