My gaming group and I arrived sorta late to the arkham scene, but have become addicted to playing the game.  We started playing around October, and picked up Dunwich, King in Yellow, and Dark Pharoah around christmas.

We recently tried to pick up Innsmouth, but haven't been able to find it anyplace.  We grew additionally concerned when we noticed that FFG itself was showing the product as "out of stock" (not sure what that means regarding future availability).

Anyone know a reliable online store where we may be able to find a copy?

You can find several copies on ebay. =)

Have you tried Amazon? Anyway, the product is Out of Stock, but not Out of Production, so I guess it will be reprinted. Not so sure whether sooner or later, though.

Sorry, I think I bought the last $40 copy from Amazon.  I've been watching the price and noticed that the Innsmouth Horror was only $40 and there was 1 copy left at that price.  The next price jump was $60.  I bought it and the price went up.  I didn't want to miss out.  Keep checking the prices in case they restock and go back down in price.