I use the
Reading List plugin for Calibre, with that I keep track of:
- series I'm reading (which books I still have to read)
- series I think I might like (first book of series)
- series waiting list (of which I've read the first one or two books and I decide to continue with as soon as I've finished a series on my "active" list)
- stand-alone books I soon want to read
- books in my 2013 classics challenge
As for finding out if a book that looks interesting is indeed interesting/on topic I download a sample if available. If a sample isn't available I look for reviews.