This index has commentaries and material on Judges.

James Van Dine – Analysis of Judges 20 pgs offsite

Constable – Commentary on Judges (b) 516K (134 pages).
Constable – Judges 504(b) (129 pages)  
Keil & Delitzsch – Commentary on Judges (b) 1.2 MB 
(350 pages).
Jamieson-Fausset-Brown – Commentary on the whole Bible (b)  48.8MB (3949 pages) page 452
Gray, James – Concise Bible Commentary on Old Testament (b)#Judges
Maclaren – Commentary Dt, Jos, Judg, Rut, 1-2 Sam, 1-2 Kings 1-7 (b) 1.6MB (441 pages) 
Henry, Matthew – Commentary (b) Set: Josh.-Est. Vol.2  12.6MB (1701 pgs).
McGee – Joshua, Judges, & Ruth 569k (17 pages).