About a week ago I noticed literally a puddle of water in the left passenger foot wells both front and back. Now the front left seat was bone dry and the back left was too, and the window seals are fine too. Any idea what the problem is?

Unless it rains upside down exclusively under my car?

Pop a look under the car and see if there are any body plugs missing in the passenger's area

Common is a leak from the heater vent infront of the lefthand side of the screen if you lift the bonnet and remove the black plastic windscreen trim you will see the vent hole. around the hole can rust or the seal can be damaged. Its directly above the left footwell up behind the glovebox.

Thanks guys!

What Crackajnr said, same problem I had, I used expanda foam to fix this problem (just use some degreaser and clean the area thoroughly first) and this should help solve the problem. Make sure you seal right around the vent shaft on the outside. Do not put any on the inside of that hole or you'll screw up your fan and you can say good bye to air con!

I had same problem, it was leaking through vent hole. Seal was not sitting properly so i used silicone to close all gaps but that solved only half of my problem. It continued leaking but not as bad. I found that my windscreen was leaking as well so i had it refitted and it did stop leaking completely.

The other possible ingress point ares the dabs of heat curing putty alongside the hood hinge mounts.
Just open up the cracks with a sharp screwdriver and put some windscreen sealer in.
I took a year to find that this was the cause of my problem after checking many other areas.
Gerry