Thrifting is a tough one. I guess I would say I have a love/hate relationship with thrifting.
I've been dedicated for 10 years or so. Started when I was in about 9th grade and was looking for vintage sneakers mostly, vintage sports apparel (Starter jackets, etc.)
I've been through a lot of phases in the way I dress, but have definitely settled down to appreciate more traditional menswear. No matter what I was into at the moment, Starter jackets, vintage Polo, etc. I always turned to the thrift stores. I've found some awesome stuff like a 1992 Polo bear sweater, countless pairs of nice dress shoes (Allen Edmonds, Ferragamo, etc, even found 1 pair from Edward Green) I've got a couple dozen of nice shirts from Zegna, Canali, Brioni, etc. Nice pants, sweaters, etc.
As mentioned, it gets frustrating since it's so hit or miss. One thing is for certain, there will always be more disappointing trips than successful ones.
I buy anything I can that's worth money, keep what fits me and sell the rest to help pay for school. I don't make any high figures like shown on Styleforum, but I make enough to pay for my textbooks so i'm a happy camper.
Wj4, you're in Los Angeles, correct? I think I posted about this a few months back, but Los Angeles has been very disappointing for me when it comes to thrifting. I don't have a car while i'm there for school, so it's tough to get around the entire city. I've been limited to taking the bus to Santa Monica, but the Goodwill and Salvation Army stores there are certainly a waste of my time. I had dreams of finding the coolest stuff, but now I look forward to coming home to San Diego so I can go thrifting

I'm sure the good stuff is around, just need a bit of luck, I guess.