I finally found a tailor! Yea!!!
Fatemeh, the owner, is always here and she is SO nice! I've had several things altered here already, ranging in complexity from the hemming of a pair of dress pants to the total refitting of a long, complex, embroidered dress skirt from India.
Everything has turned out lovely, and the prices are great, too ($9.50 for a pair of pants is just fine with me). They'll even rush orders, if you need it.
I highly recommend this place. Just don't tell too many other people, or I won't be able to get my same-day alterations :)