I only have sparse pieces of Electric Wizard but I would recommend the album before "Witchcult" called "We Live". If you can find it the EP "Supercoven" is a bit of a blast and it's generally considered that the "Dopethrone" record is their definitive work.
If you want to check out similar acts then Sleep is a very good recommendation, the bands following Sleep, High On Fire (very metal but still doom) and Om (very hippy) are worth looking into and the earlier and later works by Cathedral might be to your taste.
For further doom adventures you should pop over to
D.F.F.D - Doom Forever Forever Doomed.