One week until I leave for Buenos Aires (for a 5-week stay), so I'm making sure I hit all of my favorite Argentina-focused websites for last-minute revelations/tips/etc. Not surprisingly, Trip Advisor has been an invaluable resource, from its reviews of lodgings to its forum full of BsAs experts. Without those travelers' and residents' posts, I would have had no idea about porteños' idiosyncrasies regarding use of cash (crisp, unmarked U.S. bills for short-term rentals, thank you very much), I'd be clueless about ATM limits and I'd be wicked confused about the Argentine kissing culture.
I've returned to a podcast I used to listen to a few years ago: Desde el Baño. It's no longer updated, but the posts that remain are fantastic for adjusting to the Argentine accent and learning some lunfardo slang, which was the podcast's main mission.
For news, I've been checking out the biggie newspapers, El Clarín and La Nación, mostly via their iPhone apps/versions. There also are some great smaller online publications, such as The Argentine Post and The Argentimes. Interestingly, Buenos Aires also has a really high-quality government website with a ton of good stuff for visitors, including about a dozen blogs. Lately I've been trying to stay up to date with the tourism blog (duh), available both in Spanish and English.
And while news is interesting, I've learned a lot from personal blogs, notably two run by Americans: Good Airs isn't updated super frequently but its archive offers an interesting view of how the country has changed during the past few years. And the newer Tourist to Townie has some great tips and insights from a 20something packing a job, language classes and as many side trips as possible into his stay in the city.