Spend as much as you can for a quality set up now.
4 bulb t-5 over a 30 gallon is the minimum effective lighting in my opinion. Plus the more bulbs you have the more you can adjust the lighting to your preferences.
http://www.reefgeek.com/lighting/T5_...ight_Fixtures/
Also, several local stores carry different brands and levels of lighting in store. I know Aquarium designs had a decent selection of t-5 fixtures