Brewers supply group. They have just about everything. Prices are a tad higher then some but you get service. They hide candy bars in malt pallets. You know how awesome it is for a brewer to be slugging it out with 15 50lb bags of malt and find a candy bar? It's like finding a candy bar!
Mid country malt supply. Malt and sugar. They have some of the better Belgian candy syrup.
Briess malt too, there malt is ok but they send out these chocolate malt balls that are to die for.
Cargil for malt. Nice people.
HopUnion for hops. 5 year contracts are the norm now a days. The spot market is....spotty at best.
Barth-haas for German hops. Again it's either 5 year contracts or strisselspalt hops.
Yeast? White labs is the industry standard. wyeast is good too. BSI has some more rare strains.
Cleaning chemicals it's ecolab, birko, delta-formost, or local.
Granger for parts and stuff.