I doubt you'll be able to find one. It would take much much more effort in writing a tutorial then actually building the application, while building the actual application is much more (potentially) profitable.
And anyway, this is not a very effective way of learning, IMHO. What you should do instead is, learn the basic, create small sites / applications, then gradually expand them to bigger ones.
Once you get enough knowledge of the language, it doesn't really matter what type and what size of application you are building, you'll be able to do it, as long as you can afford the required time and effort.
Of course along the way you may find problems that you can't solve, but being such a popular language, you'll be able to easily get help from other PHP programmers.
So my advice:
- first learn enough the basic of the language
- then start implementing yourself, starting from small applications
- ask for help when you come across specific problems. The more problems you get, the more you learn.