Pretty much what it says on the tin...!
If you are interested in discovering some fringe artists or lesser recognised artists this is a great book to get you started.
It neatly divides them up by genre so if you feel like discovering some unkown folk band, singer songwriters, prog rock or psychadelic groups its easy to find and delve into.
Some I wouldnt class as 'hardly heard music' - eg Nick Drake, Yo la Tengo and Pavement (i even saw someone in leeds last week with a pavment t-shirt on). But the premise is that these bands despite having cult followings are not widely recognised.
but being a music geek and keen to find new artists I found this a great guide to point me in the right direction.
The writing is interesting and informative - never too much info, drifting off the point or an overload - plus the playlsits are a good starting point for artists you have never heard of before...!
Plus the author even revisits forgotten albums by major artists and also points out the artists who could have been huge but didn't make under the titles "...(Insert obscure band band name)...they could have been the Beatles/Oasis/Rolling stones/Led ep etc'
Overall - pletny to go at - well informed, arranged, presented and written. Very enjoyable.