I found 4 oz. of xanthan gum for $3.06 at this website:

http://www.barryfarm.com/thickeners.htm

They have lots of other cooking products, too.

I also found it on Amazon.com, but at a higher price and a larger quantity. It's also available at the Country Sun grocery store in Palo Alto CA.

I found tamarind paste at an Indian grocery store on El Camino in Santa Clara CA (near Lawrence Expressway).

For what it's worth, my jars of Woody's list tamarinds as one of the ingredients. Also if you look at the ingredients on the Lea & Perrins Worchestershire Sauce bottle, it lists several of the same ingredients that are listed on the Woody's bottle.

Finally, in today's San Jose Mercury (8/4/07 - House & Home section, last page - in an article about organic alternatives to Roundup for killing weeds) there was an article that talked about "pickling vinegar" that's a stronger solution than regular vinegar (10% to 20% vs. 5% for the regular stuff).

Janet