Mrsnuff.com is pretty much it for a supplier to the US.
As to suggestions......it depends on what you are looking for. Fruit with or without menthol, just tobacco with or without menthol, herbal or white/energy snuffs.
I'm very partial to Viking Dark, Viking Peach, Poschl Sudfrutch, Poschl Brazil A, Poschl Perlesruter, and several snuffs of my own make including one made from HH Old Dark Fired. Oh and anything made by Rosinski is top shelf stuff.
Some will be harder to take as a beginner due to grind and moisture levels.
Please feel free to ask anything about snuff someone here probably knows.
Jim