Current edition available in Lexis+ and LexisNexis Digital Library
Many Illinois handbooks can be found in Westlaw, within Secondary Sources.
Most recent edition available in Westlaw
OR
The Illinois Practice Series set is in Westlaw.
OR
It is a large, multi-volume set containing both general & legal subject-specific volumes/materials numbered sequentially (selected examples are included below).
The current editions of these handbooks should be in Westlaw.
OR
Current edition is available on Bloomberg Law.