"The Official US Casino Chip Price Guide" has lotsa GREAT pictures & there's a new issue (the 4th) in print right now. The Chip Rack (TCR) is currently & feverishly being updated (11th edition) by its new owners with the intent of being published before next year's convention at the end of June.

The Chip Rack (which covers Nevada chips only) uses the letter system assigning "values" to chips (like the "L" rating you asked about). Both guides are invaluable tools for the chip collector.

Steve B