If you haven't already familiar with it, do a search on the Minion method for charcoal. You probably won't have to add any.
That being said, I have a very long CHEAP ASS pair of tongs I bought at a thrift store. They are not even stainless and a bit rust now, but I only use them to pick up coals that fall out of a basket when I'm dumping coals from a chimney into baskets. I also use them to place a couple extra coals here or there on occasion. Before that, I used to just kind of try pitching them over to the other side. I also have a Weber coal rake that I found cheap at the Weber store in Palatine one day. Otherwise, I'd probably be cheap & go the route another member suggested. Buy a cheap hoe at a garage sale (for a buck or two) and cut down the handle. Perhaps grind the corners a bit and use that as a charcoal rake. Bonus is you get to make the handle as long as you like.
When I've used the water pan with liquid and wanted to add more, I've used either a funnels for adding water to a Christmas tree and also a beer bong that I found at a garage sale. Both work pretty decent.