A new store opened up in West Chester a month or two ago. Called "A Taste of Olive", located at the corner of High St. and Miner (one south of Market), it specializes in olive oils and balsamic vinegars.
The oil is in vats and you can taste them before they pour you a 750ml or 375 ml bottle. A lot of them are flavored (with mushrooms, or garlic, or rosemary, or a whole lot of other things) but myself, I stick to the plain ones. My favorite is a greek olive (Kolamata?) grown in California. They seem to have a lot of oils from olives grown in Australia.
They have a selection of balsamic vinegars, served the same way. A lot of them flavored (once again, I stay away, I prefer the pure product).
There are also a handful of other products -- walnut oil, salts, flavored salts. Today I saw some fresh bread from the Three Little Pigs sandwich shop up the street. Haven't tried it yet, but it felt very fresh.
If you want to give oils or vinegars as gifts, the packaging is very well suited to that. Bottles are decorated with their logo, and sealed after they fill them for you. Tag over the neck, and gift bags. If you just want good oil because you're a foodie, that will mean less to you.
They recycle bottles and they have a frequent buyer program.
I wish them well. They are a nice addition to the food scene in an otherwise arid suburb.