This is my guide for jungle alistar, alistar is a really strong champion with tons of peel and he is really tank. With the changes to spirit stone I feel alistar has a strong chance in the jungle instead of just as a support.

For runes i go standard armor yellows, mr blues and attack speed reds. Quints however i got 2 armor pen quints and 1 life steal quint. Life steal helps with the time before getting spirit stone since alistar's roar doesn't heal for that mutch without a lot of ap.

For mastries i go 0-21-9 since you do not need anything in offense for him to do well in the jungle. The utility tree is good since you need the extra seconds on your buffs since alistar is fairly mana dependent farming and ganking. Movement speed to move around the map and gank with just tier 1 boots.

For items I tend to get an acient golem for my jungle item, for boots you can either get merc treads or ninja tabi or even swifty boots if you want to move fast and they have a lot of slows. After that i tend to get a sheen and build a trinity force since it works well with his kit and gives him tank stats with the health and mana, you can get ig but i don't recommend it. After trinity force i go full tank with a sunfire cape, spirit visage and warmog's.

At level 1 you want to put a point in your q since it is your main clear skill and is good if you're getting invaded. You can easily flash q then have your team follow up for a first blood or even a double kill. You need about 3 or 4 points in your q before it clears camps really fast you also need a spirit stone for the extra damage.. After that you want to max out roar for the heal since it is good in segueing

For spells i run the normal smite and flash but you can run ghost instead of flash if you want

Alistar in ranked is mainly seen as a support but i think he can be played in ranked as a bruiser tank to soak up damage and peel. If you ignor him he can headbutt you into his team or knock you up so you can't do anything.

Pros
Strong champion
Tanky
CC
Peel
He has a heal

Cons
His headbutt can be used to help an enemy escape
Squishy early game
Cannot 1v1 without a sheen

When ganking you want to walk around them and when the try to run you want to headbutt them back into your teammate unless the teammate is low health and the enemy laner can kill your laner.

I highly recommend working on the legendary QW combo :D

That was my build for Alistar the minotaur, he is a really strong jungle a tank and probably my favorite champion.