I'm super lean too.  I've found stretchy jeans in the section for young girls that fit the way I like.  The way I test the stretchiness: if the waist is stretchy, (I just visually can tell the right size / stretchiness combination), the jeans tend to fit pretty close to the way I like.  (Some stretchy jeans have little or no give in the waist - I don't bother even trying those on.)  I keep an eye out for Buffalo brand - they seem to have a lot of different styles.

I usually cruise used and second time around type stores.  I've picked up new designer jeans for five bucks. It doesn't hurt if you can mod them too.  If the waist is just right you can play a bit with how high you wear them for boo-t axentu-A-shun.  Add cool euro style spats or knee-highs and you will def get noticed.

Good luck!

Being 6'1" and a size 8 jeans makes it difficult to find the proper length 8t at most places.I was out with my exwife doing some shopping and she suggested we try this store called Vanity http://evanity.com/. This place was awesome. They had all sorts of dress pants their size 9 x 35" inseam and jeans in a 28"w 37"inseam. I also bought a couple of shirts. Definitely a place for tall women to find nice trendy pants.They were on sale and affordable.
I have heard of Tall Girl Shop http://www.tallgirlshop.com/us/ I am thinking of going there this weekend.