This was one of the tutorials I used! It's a really good one!
There seems to be less and less sweaters at the thrifts now since they've brought out/moved up all the spring/summer clothes. Some days/weeks are just a miss, but it's always good to check frequently. Never know what you might find.
Are any of you on Ravelry? There's soem groups on there dedicated to unraveling sweaters and being thrifty. Thrifty Knits & Unravelers are just two of them.