I think I could also do with a dictionary of Vulgar Latin… occasionally, I come across etymologies of French, Romansh, or other Modern Romance words, but they typically go to Vulgar Latin.
The dictionary I have is of classical Latin, and I think it’s a bit too “pure” for these purposes.
For example, apparently Romansh “pledar” (to speak) comes from PLACITARE, but my dictionary has no entry for that so I’m unsure what it was supposed to mean in Latin.
Or how French “commencer” is said to come from COMINITIARE — also not present.
At least AFFLARE was there (the root for the Sursilvan word for “to find”).