Please call Stella. Ask her to bring these things from the store: Siz spoons of fresh snow peas, five thick slabs of blue cheese, and maybe a snack for her brother Bob. We also need a small plastic snake and big toy frog for the kids. She can scoop these things into a three red bags, and we will meet her Wednesday at the train station.

According to some, the paragraph above contains nearly every sound in english, (oy as in oy vey is missing, there is only oy as in toy.

You can hear it spoken by 260 speakers of english, both native and non-native, at
http://classweb.gmu.edu/accent

GMU is George Mason University, in Fairfax, VA. Most of the samples were collected by Prof Weinberger, or his assistants, and if you think your accent is missing, you can arrange to submit it.

You can compare the samples to the University of Kansas's collection, (not all the same sentence) which is part of the their theater and acting department..which is intend to help actors get accents right..
http://www.ku.edu/~idea/index.html