I LOVE having live plants in the tanks in my dorm. It's really helped keep the water clean, which is really nice during times like finals week where I'm super busy and would have trouble doing more frequent water changes, and my bettas really seem to appreciate them. Here's a pic of the 5.5 gallon betta tank at my work (not technically mine
exactly, but I've more or less told everyone that anything they want to do to with this tank has to go through and be ok'd by me first) - since I'm only at the office once a week, it had to be super easy to care for and low maintenence. It gets one 50% water change a week and the water perameters are still well within safe limits.
Just take note that this was the first day it was set up and hasn't grown in yet. The plants in here include hornwort (careful with this plant, if it isn't happy it will shed needles like mad - otherwise it's great), water wisteria, green cabomba, anubias, and compacta.
I got all of these at Petsmart, but you do need to be careful when getting plants from both Petco and Petsmart as they will label semi- or non-aquatic plants as aquatic. To keep the plants from messing with your water quality in a bad way, just remove any dead plant matter so it doesn't decay and release toxins. When I have to move my tanks (all four *sigh*) I just drain most of the water so that the roots and substrate of the tank are still wet. No need to uproot anybody