I recently looked at a list of items currently in the PBE, and I was disappointed to not find any items that focused on ad bruisers who required some mana. The way I see it, there are currently are three mana items that AD casters can get: Manamune, Frozen Heart, and Banshee's Veil. The way I see it, getting Manamune first reduces your tankiness significantly while the last two items offer no damage. I was looking for something like an AD Rod of Ages, and I thought it should be something like this (it has the current PBE item costs and stats):
3070 cost (Catalyst+Pickaxe+Long Sword+580g)
UNIQUE Passive: 10% CDR
I noticed that Spirit Stone did have a build path that included Mana Regen and AD, however, that would mostly be for junglers as Spirit Stone is pretty unviable in lane. So, here's my try at a Mana Regen/AD/Utility item for AD Casters who would go top or maybe mid:
2740 cost (Faerie Charm+Faerie Charm+Vampiric Scepter+Pickaxe+705g)
15% Life Steal
15 Mana Regen per 5 seconds
This could be pretty useful for some extra utility at a low per-stat cost, while still giving you valuable AD.
TL;DR: AD Mana items are still lacking, let me know how my suggestions look.