While I was looking for a page where logarithms were explained, I found this webpage, and there they have our whole unit (because logariths are powers, and you must handle them right if you want to understand logarithms). I think it's a good explanation.
LOGARITHMSI also found this videos about logarithms with a lot of examples and their properties:
Introduction to logarithmsLogarithms properties Part 1Logarithms properties Part 2I'd also like to propose some problems. There aren't many problems related to logarithms, so mine won't be very difficult or elaborated:
log
a y = c; log a y^2 =??