My toolkit:
LT Spice IV (free) for simulation - admittedly not much yet
Diptrace (free/paid) for schematics and PCBs. I'm on the free "hobbyist" version which is 500 pins, 2 signal layers, unlimited plane layers.
GerbV for viewing gerbers before manufacturing
I'm not sure how good integration will be between Diptrace/LTSpice to be honest as I only used them separately, although Diptrace can export in about 8-10 different netlist formats. Diptrace is pretty week on the project management side (e.g. you basically just save all your files in a folder and manage them yourself) but other than its pretty good to get started on.
In the past I also used
Eagle which I think is ok, but a quick search on the forum will show you its kind of disliked
. I just installed (dual boot) ubuntu on my windows pc to try out kicad, geda etc but as I don't have a wired keyboard I can't actually access the installation (the keyboard is not recognised until windows loads up so I can't select the Ubuntu partition!) I have tried Kicad on my windows machine but found it so-so.