Yeah, Schirmers is really great. I love the arrangements in it!
I'd also recommend, "26 Italian Songs and Arias: An Authoritive Edition Based on Authentic Sources"... If you get one or the other, you really don't need both, because they have a lot of the same songs... I just find that this one is great for the beginner, as it provides super translations, and pronunciation guides.
http://www.amazon.com/Italian-Songs-Arias-Authoritive-Authentic/dp/088284489X/ref=pd_sim_b_title_6 I'm not sure what colour of voice you have, but here are a few that I started with:
Se' tu Mami-Pergolesi
Nel Cor Piu Non Mi Sento-Paisiello
Caro Mio Bien-Giordani
Those are all fairly standard beginner arias, and if you like, I have mp3s of them and a few more if you want to hear what they sound like. =D