My MiL is the ricotta queen. When I first joined the family I mentioned some ricotta (which, in her Southern Italian dialect sounds like 'rrri-GOT" with a very faint "uh" sound at the end, more like the releasing of the long-held "t") and she asked what kind, the look on her face told me what she thought of most store brands. Thankfully, I learned.
One easy test is ingredients: no vinegar! no starches! no gums! Good ones usually have just milk, whey and salt, IIRC.
This site has a nice discussion about the addition of extra acid and why it's better not to do. And, if you make your own cheeses and have why leftover, you'll even learn how to make your own.
I concur that Whole Foods is very good. aschie30, I seem to recall that some Dominick's used to have a good one, so maybe that is the same still. I also seem to recall she doesn't get it there anymore; not sure if there isn't a Dominick's close by her or if the one she goes to has changed suppliers.
For price and quality, our favorite is at A&G. They have two or three kinds. One is drier and one is more wet, but not too wet (it doesn't have to be drained). They will let you sample them to decide which you want. The price is excellent.