We use a huge number of idioms. Proverbs are not used as much as they used to be, but are still a feature of language. The most complete selection would probably be in the Oxford English Dictionary, which has ust about everything ever used in the English language. It costs a fortune in book form, but much less in electronic forms. The Cambridge Dictionary of Idioms is pretty good too.
Online you can access the Cambridge dictionary here:
We have a growing collection on the site:
There's also the excellent www.onelook.com that searches hundreds of online dictionaries.
These should be able to find any idiom for you.