Gui -
I am not sure what you mean by the NASA logo with "the bubble letters with the white strips running between them." Is this the one you mean? (this is known as the NASA "worm logo" - officially, we are not supposed to use it any more; the only official NASA logo is the "meatball" blue splotch background logo). If this is the one you want,
e-mail me me with your contact info, and I can send you a high-res version tomorrow.
-dave