For me, presentation is everything. The cookies inside the box can be good but they are not great unless they are presented well. I spend lots of time (and extra loose change) on ribbons, boxes, tissues, bags,anything that adorns a box and gives it a life of it’s own.

Nashville Wraps – This is my favorite place to buy boxes. I personally like these and these. I also love their ribbons (the grosgrain)
Baking Boxes is another great source. They are a bit more expensive, but their selection of colors are spectacular.
Papermart is a fabulous resource and if you live in Los Angeles, they deliver the next day. I buy their coffee bags in bulk as well as their cellophane bags. And their ribbon selection has a wide variety of both size and color. Crimpled paper shred is a good alternative to styrofoam popcorn for filling crates, tins, and boxes.
More sites that inspire me:
Fancy Fleurs – they are one of the few sites that has colored parchment/tissue.
Atlantic Sales – great for tins, but you have to buy in bulk. Try and piggy back your order with a friend.
Specialty Bottle Company – I love this site for vessels of all kinds.
I hope this helps.
Happy gifting and baking!!