ToDoList is an opensource application on http://www.abstractspoon.com/ hosted at codebetter.com. It's a simple easy to use and has almost everything you were looking for except true attachments. They have something close; a link to location(file,folder,website,email, or task) that once it's filled in has a view button that launches the location.

Work for near free (like minimum wage or even less), but not free. You need to get paid. Look on job boards like guru.com and hireageek.com and bid on projects at cheap rates. Then you can put on your resume that you contracted to these companies for the projects. Do as many short ones as you can. Ask permission to use them as references and if you want to use them as a reference, remind them, ask them a second time and warn them that you put their name out there as a reference for you.

This actually will get you experience and paid (some).

Other than that, work for free on an opensource project. Find books/blogs/articles on how to go about that.