I am guessing you have 2X 54 watt T5HO? The Wet Spot in NE Portland had the best selection of plants of the LFS in Portland when I visited down there last spring. Your fixture with two bulbs will put you in the 'High Light' category. The good news is you should have sufficient light to go just about any species; I hope you are running CO2 or algae may become an issue fairly quickly. Start with a short light period, maybe 4 hours total and increase slowly over several weeks.
Pick up some easy plants to start:
Hope this helps!