Just be careful if you already have softies in the tank because some of them emit chemicals designed to inhibit sps growth, and other have sweeper tenticles that will sting the Acro and cause damage. I agree that stag horns (bali Slimers, blue stags, evergreens, etc.) are good first timers, and if you aren't hung up on it being an Acro, birds nests, cats paws, and montipora are all relatively easy sps to start off with. I would just avoid any of the deep water acros or echinata and make sure that whatever you get is a well established frag that's encrusted the plug. It's amazing how much easier it is to start with a frag that's already growing on the plug than to go with a fresh cut piece. Just make sure it's securely attached and is in an area with relatively high light and strong random flow.
Every Acro sp. is going to act differently in different tanks, so a little trial and error may be necessary to find what works best for you. Just don't keep it out of the water too long and once you place it, don't touch it! Read up on acclimation and dipping too, it's important to add it to your system the right way the first time. While they can be a little more pricy, I happen to think that Ora red planets are great beginner acros. They grow quickly and can handle a wide range of lighting scenarios (in slightly lower light they actually keep a beautiful green color on their skin). Just get a healthy frag and if your system is sufficient you'll be fine! Good luck and welcome to the addiction lol.
