Dan absolutely ships to APOs, Gene! NO worries there. Honestly, pretty much anyone who will ship USPS will ship to APOs. Famous will screw you out of their "free shipping" offers because that is with UPS, but they'll still ship to you USPS, you just have to pay a bit extra. CI, however, WILL ship to APOs for free still when they have free shipping offers (like the Joe's Daily Deal, and what not). I think CI is the best all-around or troop support
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Nice Ash, Smoke Inn, heck most of the US distributors will ship to APOs.
As far as "other" suppliers, feel free to PM me.
But overall, it's been much better than I thought it would be. You just have to ask people to package everything extra well (I do this for shop/website purchases as well as individual) and for individuals I ask them to include a Boveda mini-pack if they happen to have one, as you never know if a pacakge will take a week or FOUR weeks!