get yourself into tripadvsior.com for local advice each destination
there are some really helpful experts there
take a look at luxurylink.com community forum--we have several members who have spent time in Patagonia and Chile particularly. not that you want to buy any of their hotel packages but you can find out about a specific town/area in their destination "guides"
I;'d also poke around for current issues of Arthur Frommer's Budget Travel
We only did a few days in BsAs, staying in apt in Recoleta w/side trip to Colonia (bust) and woudl gladly go back to eat more of their fabulous beef and dare I say, I love Malbec wines!! We found the Evita Peron Museum very fascinating--Boss, as well--he's very political!
Check in w/your local wine reps and see who can refer you to special tastings, etc (if you like winery stops) for both countries
Hope that helps a little.
PS--don't forget, $140 tax for each country via air but good for life of passport or 1yrs max