A good place for cotton is walgreens or CVS. I get kanthal either from Lightening Vapes on ebay, or Temco on their website. As far as tools, I just use stuff I have laying around. Nail clippers, drill bits, small screwdriver set I think we got for a couple of bucks at Walgreens. Strong dreading glasses so I can actually see the coils (though if you are young you might not need magnification).
I don't know a good place to get a Russian 91%. There are a lot of good Kayfun/Russian clones out there. Consider those as well. The most popular clones seem to be EHPro, hcigar, and tobeco (as far as I can remember). Take a look in the rba rda sub forum. Lots of info there.
Rebuildable Atomizer Systems