what about sphering using just agar and oil? any tips?

yeah, Ive made plenty of sphere's before but it seems futile to know the technique if Im just following someone else's recipe. Ive actually talked to Dave a few times about it, and theres only so much you can absorb in one conversation with that guy. thanks for the links though, there should definitely be some answers in there

I believe what you are speaking of is the use of hydrocolloids. You should check out this primer by Chef Dave Arnold who teaches this stuff at French Culinary Institute.

http://www.cookingissues.com/primers/hydrocolloids-primer/

It's technical but in an educative sort of way. I think you'd benefit from reading all of it, but you can skip to the section "Recipe Formulations and Measuring" if you want.
The rest of the Cooking Issues blog is a great source for all things where science meets cooking...meat glue, sous vide cooking, etc.

Look here:

http://en.molecularcuisine.org/forum/showthread.php?tid=51

then join.

Who are you trying to impress?

I've never tried any spherification, but it sure sounds like interesting fun. If you don't want to invest in a pH meter, why not get some pH paper? It's very affordable.