I started playing Singleplayer, and omfg this game is epic. (even though it was made over a decade ago)
I went with a Necromancer, im currently level 5 just starting the 3rd quest on Act I.
As i level up im putting 2 points in eng, 2 points in vit, and 1 point into strength. Dont know if this is good or not, its just how im going to roll. The reason Im putting 1 point into Str is for Wep Reqs.
As for my Skill Tree, i have 2 points in "Skeleton Summoning", 2 points in "Skeleton Mastery", and 1 Point in "Teeth".
I dont really know if im going to use golems as i already am using skeletons. (any help with that would be appreciated)
Im only going to put points into the first Curse spell, as it helps when im using my Summonings and once i get the "Revive" spell.
As for the Bone and Poison spells i think i might run with the Bone spells, as "Bone Spear" sounds epic
Bone Spear is pretty epic. Its great for narrow corridors as it pierces through enemies until it hits a wall. Its a very linear attack, which is its downside.
Amplify damage is a good spell to compliment skeletons. I'd even suggest Decrepify. But amplify damage is good too!

Golems are just kind of fun to have around. They can be pretty useful early game, especially blood golems in Act 3 but once you run through the game on Nightmare and Hell they become somewhat useless.
You're going to have a lot of fun with skeletons, especially when you reach higher levels as you'll amass an army. Depending on your version of Diablo, you may be able to get more skeletons per skill point.
What version is your game?
EDIT: When I made a skele-mancer I put all my faith into my summons. As long as your skeletons can hold their ground you don't need to physically beat down anyone with a wooden wand.