I wonder if i should start with deadhouse gates though.
I did, purely by accident, but didn't realise until about a third of the way through when characters started popping up, or being referenced, without any explanation to them. Still an enjoyable read, but I wouldn't recommend it as a starting point. For all the criticism
Gardens of the Moon gets for throwing you into the middle of the action with no lead-in, it's a far cry from actually starting in the middle of the action with no lead-in.
The other alternative is to start with
Midnight Tides - the first four books centre around one, very large set of characters, locations, themes, and events.
Midnight Tides is almost entirely new in every department, introducing a second branch to the overarching story that converges around book seven or eight. It's definitely a more accessible book than GotM, and will give you a vague idea of the world as a whole, its mythology, and some backstory to what's going on. From there, though, you definitely need to go back to GotM and read things in order (the MT story continues in the sevent book,
Reaper's Gale).
All that said, I'm going to echo
@nixie and recommend starting with GotM.