buying them at the Grand Exchange
Magic lamps are awarded from Random Event boxes.
No. Even the lamps don't work.
druidic ritual
A lot of quest give you exp lamps. You can also check the reward of the quest before you start it.
Bandos is
Teak Logs.
I have placed a link below that should direct you to a page with the answers you seek.
Not that I know...the only way to get them is to participate in a random event
The only ones I know is to beat random events.
the easiest way to train strength would be the Soul Wars minigame.
You get experience lamps of fairly low value from random events. You also get some higher-level experience lamps from certain quests. Recently, the Squeal of Fortune has been added; it also offers experience lamps.
That would be a goblin.