[Pharo-users] Package browser?

I am attempting to do the Pharo by Example book, but a package browser (which is used in the examples) is not in the 1.1.1 or 1.2 image. Should I still use categories? If I create a package in Monticello browser I am not able to add classes or anything (not as far as I could see). Just starting out using Pharo, so apologies if these questions are already answered elsewhere.