It's easy to have color in an African cichlid tank! The easiest fish that will add color to your tank and can be found in just about any pet store is the Yellow Lab (Labidochromis caeruleus). I also love the Acei (Pseudotropheus sp.). They complement each other well in color contrast and have similar 'semi-aggressive' temperament.
I'm not sure how familiar you are with cichlids, but there are primarily two rift lakes (there are others) many hobbyist use: Malawi and Tanganyika. It's best to keep Malawi or Tanganyika in your tank and not mix the two. In my experience, a lot of the fish in pet stores are Malawi and Malawi cichlids are what I'm familiar with. Lake Malawi cichlids can be subdivided into three groups: mbuna (rock-dwelling), Haps, and Peacocks. It's best not to mix these different types. Mbuna are my favorites.
There are SO many different species. Kenyi, Bumblebee, Auratus, Red Zebra to name a few, and all those are pretty too (more aggressive).