Oil needs to be as warm as possible before dropping the oil. The hotter it is the more viscous it is and the more crap will be suspended in the oil.
I use a vacuum extractor pump. $50ish odd off Ebay. Saves the sump plug threads and reduces the chance of spills and make it easier to decant the waste oil into disposal containers.
Skids, if you're going to run GW talk to Adrian at Liberato. 20ltr drums are the go cost wise.
I also use GW oils either Syn-X 3000 for 10w40 or Euro Energy for 5w30.