Pronunciation of ę and ą?

I looked for answers to my questions but I havent found what Im still looking for... Im a Czech and I learn Polish. These languages are quite similiar but I have no idea how to pronounce ę and ą. I know those vowals are nasal but how to pronounce these ones? And I also dont know how to ponounce ś, ć and ź. They should be softer than sz, cz and ż. Is there any video what to do with lips and a tongue like I can see learning English? Thanks a lot for your effort to help me.

Have you tried these great videos here They are not quite what you asked for, but might help.

Yep, I already saw the videos and they could help me a little. Unfortunately, there are not many good materials on the Net about Polish pronunciation. But the same I could say about my native language. Poor polish guys who want to learn Czech pronunciation on the Net. They will also find almost nothing. :)

Havy you tried ivona.com? Just let her say some words with those letters, it sounds very good and natural. Cinek