Here is a table which shows the notes of the traditional melodic minor scale in all twelve keys. Remember that the descending melodic minor is the same as the natural minor. To work out the notes for the harmonic minor, simply flatten the 6th degree of the ascending melodic minor.
To finish things off, here is a great piece by J.S. Bach from Sonata number 2 for flute and harpsichord. It is written in the key of G minor in ) time. There are many great pieces written for other instruments which can also be played on the harmonica. Look for Classical flute or clarinet pieces and also Jazz saxophone solos. Keep playing, keep practicing and play with other musicians as often as possible.