Hi fvlmasl2,
You could post same question to the RPG forum and get a better audience.... but this is how I'd approach it.
Use the DSPOBJD command - specify object type *LIB - or User lib if that is an option i the Attributes line.
for Output specify *outfile - give it a name and the library you want the file to be written to.
Then, build an AS400 Query (CRTQRY I think is the command)
specify your above outfile name - select only the fields you are interested in .. lib name, size etc
maybe this will get you started. I have done this but at home don't remember the exact command specs.
HTH, John