Dickinson has an excellent resource for beginners:
https://dcc.dickinson.edu/ovid-amores/scansion
They've been hard at work at getting a lot of resources for students on their website, like Allen and Greenough.
One resource I've long used is Rudy Negenborn's Catullus site, where, besides including different translations, he has all of Catullus scanned, too.