Congratulations and thank you for finishing this wonderful series! It has been a delight to watch, and easily one of my favourite mahou shoujo serials.
As far as other Creamy Mami works, there is a manga, two feature-length OVAs and five OVA music video thingies (I cannot think of a good name for them), not to mention the I-don't-know-how-many albums released
I have raws for the Lovely Serenade and Curtain Call music OVAs, but they are below Live-eviL quality I am afraid.
EDIT: I almost forgot, Creamy Mami also appeared in a couple of other pieces. The Adesugata Mahou no Sannin Musume OVA, with Persia and Magical Emi, which was only so-so, but the Majokko Club Yoningumi A Kuukan Kara no Alien X OVA, with Persia, Magical Emi and Pastel Yumi, was good for a laugh. The Minky Momo vs Creamy Mami special, which came with Creami Mami's Long Goodbye OVA (and Minky Momo's Yume no Naka no Rondo) was hillarious, but needs no subbing