I get my equipment and supplies from several different sources. It just depends on what it is.
Mark @Easy Clean - HW rig and surface cleaner, dual lances, fittings.
Steve Rowlett - concrete cleaner
Espec - misc fittings, sureflows, brushes, misc.
Pierce - ReadySeal
Russ/Beth - HD80
ChemistryStore.com - sodium percarb, sodium tripolyphoshate, soda ash, etc.
Xterior - Gutter Zap
Chemetall Oakite - Citric acid
Local ICI Dulux paint store - TWP, roller pads, brushes, drop cloths, etc.
Direct Safety - respirators, cartridges, nitrile gloves, goggles.
Lowes - pump sprayers, squeegees, misc.
That's most of what I can think of now.