I tend to err on the side of non-intervention, but most of my experience is with primitive breeds that lamb outdoors happily.
I would say yes, go on a lambing course, so you understand what the things you've read look like in real life. BUT there is no point buying medicines that you don't know how to use (and would be calling the vet for anyway).
I think I would go for:
long gloves
lube
lambing rope (can be made from lengths of washing line with a loop tied at each end - nice and smooth for the ewe)
soap/water/buckets/towels/light sources/kettles/other site-dependent practical thingies
calciject and syringe and needles in case of suspected twin-lamb disease (are you comfortable injecting things?)
iodine or antiseptic spray for navels
colostrum replacer/bottles (I've never had to use these so I'm not sure how soon after birth this needs to happen - milk powder can, I presume, be picked up the next day if you need it)
pens and paper for notes and records; perhaps spray marker to identify ewe/lamb families
There are all sorts of pills and potions you can add in, I gather commercial sheep have a bit less get-up-and-go so might need some more mollycoddling