there are electronic ballasts you can buy at home depot. you can not use cap and coil, or tar ballasts as they are not able to operate different types of lights.
If you dont have any experience with lighting or electricity id advise you to cut costs somewhere else. messing with ballasts and bulbs could cause major problems. light failures and bulb replacement will be the least of your worries. you could easily blow bulbs, ballasts, or worse, cause shorts or overheating ballasts and a large potential fire risk.
cutting corners on lighting is one of the biggest mistake ive seen many newbies to reefing take. The inadequant lighting allowing just one or two animals to die will negate any money saved on the cheaper lighting. Not to mention many of them will need to upgrade because there not satisfied or wish to keep more demanding critters.
If you want cheap lighting solutions, get a VHO retro kit. Its money well spent, as there is resale value and upgradability. Many people start out with two or four VHO bulbs, then simply add MH later and keep the VHOs.