You can get them on Amazon or any other multiple places on the internet. I am getting mine here because they have a Nebraska Shaped one that I can't pass up.
I might warn you I just went to order mine when I got home from work and it is $10.95 shipping in handling. Ouch!! That broke the camel's back for me. I got a cheaper one on amazon that comes with a Jalapeno corer as well. Not as cool but my wife will be happy with the more practical amount.
Here is the link: http://www.amazon.com/gp/product/B001LF3SV6/ref=oss_product
I have the rack & prefer to slice them lengthwise, fill, & wrap with bacon. If you use thin bacon they crisp up & if you use a hard cheese such as sharp white cheddar the cheese doesn't run out. Put them in an aluminum pan & smoke for 2 1/2 hours at 225. I used cheddar cheese spread in these & you can see how all the cheese ran out. It was still good, but better with a hard cheese.
In our house everyone likes the more mild peppers- that way you can taste the ingredients rather than burn your windpipe on the first one. I like to de-seed and lay a strip of prosciutto in the pepper then add some cream cheese and maybe some Cheddar (white, extra sharp) then wrap in thin bacon so they crisp up a bit. A wooden skewer can help manage them-