Ok so the main weapons systems in arsenal.... Where are the costs for their ammunition? Also I cant for the life of me find the road strips or zapper strips for pursuit vehicles. Please help i must be blind.

Road and zapper strips are on page 106 of Arsenal. What do you mean main weapons?

The vehicle mounted weapons in Arsenal, starting on page 123, I believe.

As for their ammo (for those that obviously aren't lasers or gauss), in a pinch probably assault cannon rounds. Part of me thinks that maybe the writers thought that shadowrunners wouldn't be getting a hold of a reliable source of ammo for these weapons (they do start at 15F in availability, after all).

Or they just got left out. I mean, plenty of examples of that

Well for the GM Light and Heavy Cannons, it says to use the same price and availability as the assault cannon ammo (pg. 124 Arsenal in the weapon description). For the light and heavy auto cannons I'd just use the same rule. They are all cannons after all and I think that is how they were priced in 3rd ed.
For the rest, yeah lasers use power packs and guass weapons use chunks of iron or some iron alloy. Probably the same cost across the board for those just like your pistol ammo costs the same as your assault rifle ammo.

Get them in a belt and you're good to go for Cannons? Very simple, too simple if you ask me. But I specialized in Weapon Systems in the US Navy, everything from Semi-Automatic Pistols & Assault Rifles, up to 5 inch guns, with projectiles 5 inches in diameter, and shoulder fired missiles and rockets.

This Over-Simplification is a disservice to the understanding of the scale of operations.

Yeah but this isn't a reality simulator game and most players don't have that level of knowledge. The designers have chosen to focus on a slightly more cinematic play style and have therefore simplified things like ammo down to one price fits all. Sure the real world is different and if you need a fluff reason for this just say Ares, the premiere weapons manufacturer, has cut a deal with the other corps to streamline the whole process so one size does fit all.
I mean we could track things like how much 9mil ammo you have for your Berrata and how much 45 cal you have for your Ares Predator and how many rounds of 5.56 you bought for your Colt M23. And then we could figure out how much those different calibres cost but who really wants that level of minutia? Does the added book keeping add anything meaningful to the game experience? Would most players even care? Probably not but if it bothers you enough you are always free to houserule it to your satisfaction.
Anyway, that's my 2¥ on the subject.