DnD Encounter Table Utility
With this utility, pick an EL and the columns on the right will show the number of a specific creature that it takes to make that EL. The last column is based on the last column in the DMG. It gives the CR of the creature the listed creature should be paired with.
Since the list is sorted by CR, you can select the rows that have entries and print them out to have an encounter list for any given EL.