You know what, I didn't even know an automerge existed in photoshop. I always do it manually. The process is more or less the same except that you mask the layers yourself and therefore you have more control of how the joins occur.

Couple of tips I'd like to add to the tutorial:

Get to know about Hyperfocal focusing. Focussing at infinity could cause near objects to become blurred. OK, so they'll be easy to merge but the final result isn't as nice as when everything's sharp. Focusing at the hyperfocal distance ensures the maximum depth of field. The distance varies according to the type of camera and the focal length. Check out dofmaster.com for a guide and tables which will help you. I printed tables from this site, laminated them and carry them in my camera bag. I use them for virtually every landscape shot I take.

Manually blend the joins using layer masks. Doing this will enable you to pick and choose exactly where the joins are. This helps when items in the foreground are very noticeable where there is a join. You can change the join by painting or erasing areas in the mask, therefore choosing which layer you want to be visible at that point. Use a large, soft edged brush to start with to create your initial blend, then a smaller, harder brush for the finer parts of the join. It takes longer than the automerge but I find it more satisfying and the result is usually more convincing.

Andy.