yea you can make dirt bikes street legal. rockymountain.com has street kits. you have to have headlight taillight turn signals mirrors and horn here. check with your state though. you would be better off and sell yours and buy an ENDURO bike. its already street legal and the tires are made for multi surface so they wont go bad after like 14 days.what kind of dirtbike is it? heres an example of what you will need.( top 4 items are mandatory. this is for a honda crf450r)
http://www.rockymountainatv.com/search.do so about $700 without tires. i would honestly recommend you trade your bike in and get an enduro. it will be faster top end and it will already have everything on it. light blinkers gas gauge speedometer multi surface tires and spots to put your license plate.