I am always fascinated when an etymology traces a word or syllable back to Proto IndoEuropean. While there are some resources on the Web (according unto the Great Google), I have never been able to find anything approaching a PIE glossary or dictionary -- something approaching a complete vocabulary as far as it is known. Is it simply that the field remains in too much flux to compile such a thing? Is it all too controversial? I find it hard to believe that the problem would be novelty, as the PIE theory has been araound quite a long time already. If anyone can point this amateur toward such a work, I would be most grateful.
Just my two cents (and a few links): i don't think that many historical linguists would be interested in compiling a dictionary of PIE
words in the first place. I'm wondering what would be the practical usage of an extensive PIE word dictionary. I must say i can't think of one single advantage.
It would also be quite a difficult task anyway: while linguists have established a fair amount of PIE
roots, it would be only a matter of guessing which
words were used in PIE. I'm not thinking about a bunch of core words (they are fairly well established too), but about less, erm, core-y words. Actually, i think i's
methodologically impossible to compile an extensive word list annex dictionary.
I'm afraid that you'll have to be satisfied with what exists: dictionaries of PIE
roots.
As you said, a few of them can be found on line (and probably you know the following links?):
1. still a standard work (though it is getting a bit out of date) is Pokorny's
Indogermanisches etymologisches Woerterbuch. It's available online, or rather, an extensive database based upon Pokorny.
2. another decent work available online is
Watkins' Dictionary of PIE roots.
3.
Koebler's dictionary.
4.
The Titus Project offers, apart from tons of texts in older IE languages, some links to dictionaries (right, "lexica").
Groetjes,
Frank
PS: as a minor note: Old PIE is sometimes used as a technical term, the equivalent of Early PIE!