can someone tellme how many songs can i load in a memory stick duo 2GB?

Answer 1

Assuming a song is 4-5 MB large, well, about 400-500 songs or so.
This is, of course, without anything else in the memory.

Answer 2

I'm not sure what you mean by "Duo". But use an average of 3MB per song and divide that into 2GB.

So:

(2000/3) = 666 songs

Also keep in mind that all songs on not the same size. Some will be smaller and larger than 3MB.