How to find:

SOLVENT

1. Near the water pump in Bootleg Pass: The bottle of solvent is sitting on a rock to the left.
2. In Smuggler's Cove: In the open crate to the left of the golden automaton a.k.a Baron Sizzlepot.
3. In No Man's Landing: Go to the very southern exit/entrance that leads into Bootleg pass. Start walking forward/north/up. Pass the first dock. Keep going until you get to the shipment of fog rock. When you pass the fog rock turn left and keep going until you get to the very end, where there is a lantern sitting on a crate. Also sitting on the crate should be a bottle of solvent! Picture below:

Sorry, I didn't get a picture with the actual solvent bottle ;) I had already collected it.

PLASMA GLOBES

There are only 3 ways to get Plasma Globes. Winning them in battles, winning them from quests, and creating them on the Old Mount. How to get them from the Old Mount:

1. Go to the Old Mount.
2. Navigate up the mountain until you reach the passage to the Engineer's Watch.
3. In the Engineer's Watch, there is a lightning-rod-collecting-energy-thingy.
4. Drag a piece of glass (the formal name is "Lens") onto the lightning-rod-collecting-energy-thingy.
5. You will get a plasma globe. You can only collect one a day, though. Enjoy!

COAL (Episode 2 Only)

Luckily not the fog-rock kind! There are a couple places to get coal: Certain battles, and the mine on the Isle. 

1. Travel to the Isle. 
2. Get past the guards and go inside the mine. 
3. Look around for little sparkling rocks.
4. Click on them to pick them up, you will get one coal per shiny rock you click. 

Battle Method

1. Battle the Mega Drill.
2. Win. 
3. Get coal from the reward spinner. 

1. Battle an Isle Pacifier Officer
2. Win.
3. Get coal from the reward spinner.

1. Battle an Excavator
2. Win.
3. Get coal from the reward spinner.