In the interests of equal time, I also want to link to the parish we attend when in Chicago - the lush, dazzling, and thoroughly orthodox St. John Cantius. Very similar to St. Agnes, and very deserving of your prayers. In particular, check out the slide show of the interior of the church - and remember that the pictures do not do it justice.
To paraphrase some old line, come for the beauty, stay for the teaching - you'll leave enriched beyond your hopes. Pray that more churches like St. Agnes and St. John Cantius come along. Sites like the Latin Liturgical Association's are a great resource when traveling, or if you want to find a better parish in your area.
But while the LLA has a great list of Latin Masses, there are a lot of other good parishes out there - churches with reverant, orthodox English Masses, churches that use classical music, churches where the priests aren't afraid to preach about radical concepts like sin - a church like Holy Childhood in St. Paul, for example (no link, alas). And while you can always check out masstimes.org if you're travelling, that doesn't tell you whether the church you've picked is going to be more like St. Agnes, or the rampantly heterodox St. Joan of Arc. So if you have a church you'd like to tell us about, one that meets Brian Saint-Paul's guidelines, a rare gem that you think more peple should know about, please email us and we'll share it with everyone. It's a service that's long overdue.