Dan's Dwarf Conifers
This review isn't going to be as thorough as Will's reviews but at least I'm hear spreading the cheer.
Dan's site has a limited selection but you get to see pictures of the plants you are going to buy. Shipping is a bit pricey if you're getting one plant but 3 or more and its a good buy.
Dan just put a few new selections up...very nice plants for the price!
Here are the 2 gallons plants I got from him.
Pinus Parviflora 'Miyajima'
Picea Abies 'Kellerman's Blue Cameo'
Pinus Banksiana 'Schoodic'
Pinus heldreichii 'Irish Bell'
Here is a link that might be useful: DDC