Try the Taurus PT145 or the Ruger P97. The Taurus holds 10+1 rounds in a compact frame. The Ruger is slightly larger, slightly heavier, maybe narrower, and holds 8+1 rounds. The Ruger is considered to be more rugged. Both have plastic frames that are virtually indestructable. The Ruger P97 is great for guys with smaller hands.
If you want a metal frame pistol, try the Taurus PT945. It holds 8+1 rounds and is comparable to the Ruger P97. The Ruger P90 is a great pistol with a metal frame, but is slightly larger than the P97.
The best all-around self-defense/home defense cartridge in .45 ACP is Federal's 230-grain Hydra-shok JHP. 230-grain Speer Gold Dot is good and so is the 230-grain Remington Golden Sabre. Stay away from the 185-grain stuff! You use .45 ACP ammunition to make big holes, not for velocity.
A good holster is the leather Triple-K skeleton holster. Slides on your belt and holds your pistol tightly against your hip--right where you want it. And it doesn't make you look like you're wearing a colostemy bag. You can conceal it with a jacket or blazer, or if you want to look grungy, with your shirttail out.