Click on them.
check the grand exchange.
Moss Giants are ok at dropping them.
5,213,772.4 grimy Guam required, or 5,213,773 rounded, because we all know you can not have 40% of an herb =]
Farming skill, sinister chest (in yanille dungeon) and burning vyrewatch.
The only one I know of is General Graandor, who drops three noted grimy Snapdragons occasionally. The best ways to get snapdragons are to farm them or buy them.
Chaos Druids at Taverly dungeon, just past the bat bit.
You use a clean Guam herb on some swamp tar and there you go, you just made Guam tar.
Well if you are referring to the Guam herb many npcs (non-playable characters) drop them throughout runescape.
The grimy key is used in the 'Ernest the Chicken' quest. It is specifically used to enter the small room behind the stairs in Draynor Manor to obtain the 'rubber tube'. Note that a level 22 skeleton also resides in the room.
To feed a swamp lizard on RuneScape, simply use guam leaf on raw meat to create raw jubbly. Then use the raw jubbly on the swamp lizard to feed it.
The current Market Price for Guam Tar is: 20gp.