All of the above are great vendors. Don't overlook Farmhouse Brewing in Janesville, WI. They buy in bulk and subdivide into smaller 4 oz to 1 lb vacuum sealed packages. Excellent selection and customer service. They also offer different regional combo packs of 4 oz and 1 lb sizes at steep discounts. Even though they are repackaged, I haven't noticed any degradation in quality over YCH or Hops Direct.
I've been searching in vain for some Trident hops recently and thought I had a lead on them at Farmhouse, only to discover they were out (like every body else). I shot a quick email and got a reply within minutes recommending a substitute (Triumph) which I hadn't heard of but looks very similar on paper. They gave me an approximate date for the arrival of Trident. I ended up getting the Triumph, plus a WHOLE lot more, based just upon the positive customer response.
I'll also order the Trident when it comes in a few weeks from now. I haven't done all that much business with Farmhouse over the last few years, but I'm thinking they just moved up a few notches on my "preferred vendor" list.