ok, not an exact recipe yet, but here's what my research has yeilded so far. I haven't tried this out yet, and I'm pretty much a trial and error type cook..

but some common threads from my sources:

seems really simple and quick to make. (smash is with knife handle, not to pulverize)

For chicken, use chicken broth, smash and slice the lemon grass, smash fresh lime leaves, smash and slice ginger, smash chili (I would say thai bird) . Bring to boil...add in fish sauce and sugar and soup ingredients cook till complete.

Shrimp called for water to start, and adds in a touch of chili paste. then poach the shrimp in the broth.

Garnish with lime and cilantro.

I need to hit the asian market this afternoon, if they have fresh lemongrass in I'll play around with it, my cilantro in the garden is getting out of hand and I need to use some anyway haha.

Thank you!
I really appreciate it!

"Some kids piss their name in the snow. Chuck Norris can piss his name into concrete."

ok, the version with water..yuck too bland

What I did tonite seems to have worked well.

Started with a box of the swanson's organic chicken broth.

To that I added:

1/2 inch peice of ginger, bruised and sliced
3 stalks lemon grass, bruised and cut to fit pan
zest of one lime (I couldn't find the kaffir lime leaves)
2 thai bird chili's sliced, seeded and bruised. (seed or not, and how many peppers depends on how hot you want it)

tasted that after about 20 minutes on med heat and it seemed flat
so I tossed in a bruised clove of garlic and gave it another 10 minutes.

Then I strained the broth and put it back on the heat and added in straw mushrooms and bamboo shoots, cooked that about 5 minutes, added in shrimp, gave that about 2 minutes, added in 2 tablespoons of fish sauce.

To serve, I added the juice of one lime to the bowl and sprinkled with fresh cilantro and few green onions.

All in all a decent attempt, not quite as sour as i had hoped, but I was reading that the lime zest is a poor substitute for the kaffir lime leaves. So hopefully I can find those next time.

Also when I was shopping I noticed that the asian market had tom yum paste, wonder if that's any good.