H.I.D. lighting and stock headlight problems

alright, i have a 03 cavalier and the headlights are EXTREMELY dim. I replaced the bulbs w/ sylvania silverstars and there was no dif. in intensity, just whiter color. I compared my moms 03 camry to it, and it was like night and day, at least 4x as bright as mine were. Is there any way to increase the power output to the headlights to make them brighter? i also was looking into a H.I.D. system but i heard they are illegal? i see them on bmw's and mercedes all the time. the one i want is for a 9007 bulb from hidynamic.com. anyone heard of them? good quality and such things? lemme know, i have a LOT of questions