Welcome to the world of saltwater. In a 29 gallon a pair of ocellaris clowns will do great. Anemones require mature tanks, pristine water, intense lighting, and are generally not recommended for beginners. The best thing to do is to look through the saltwater section on the right side of the homepage here:
http://www.fishlore.com/. Decide what fish you like and come back here with a few choices that we can help you narrow down. With a pair of clownfish, you'll likely only be able to have 2 more fish, 3 more max. Some popular choices are firefish, grammas, dottybacks, cardinals, damsels, and gobies. Most of these fish will stay in the 3-4" range and come in a variety of colors.
For inverts you're going to want a variety of snails, crabs, and shrimp. For snails: nassarius, nerite, cerith, astrea, and turbo. Crabs: blue leg hermits, scarlet reef hermits, sally lightfoots, and emeralds. Each of them has their advantages and drawbacks. Finally for shrimp: peppermints for
aiptasia control, skunk cleaners, coral banded, and fire.
Live rock is necessary for its biological filtering abilities. It can run from $2 a pound to $10 a pound depending on the coraline algae growth, shape, size, etc. Keep an eye on Craigslist for someone taking down a tank and selling rock for cheap.
What are your plans for the tank. What kind of coral do you want to keep? That will help decide what kind of lighting you will need.
The biggest thing you can do is research. Read, read, and read some more.