I get labels from onlinelabels.com, then use a laser printer to print them myself (they have a template that you can edit with photoshop or the like). They look great.
I used leapinlizardlabels.com for some homebrew labels for my wedding last month. The labels came out great and were exactly what I wanted. As long as you know the size and have a good image, they are really flexible in sizes and types of paper. Shipping was reasonable and I got them really fast.