Reply to Numark tt500's and SL!

hey all i just pretty much inherited some numark tt500 turntables and SL1 i have never used the program and my experiance with vinyl turntables are very limited about 6 hours at most. i believe i have the idea on how to connect. put pretty much download the program free on the computer. hook up the RCA's to the box and run the box USB to the computer? i'm not home right now or i would experiment but i figure if i can just confirm the set up i should be fine. also like i said my knowledge of vinyl set ups are very limited, the guy who gave them to me said i should just replace the needles and stylus. i was looking online and seen that these needles can get very expensive very quick. I normally use my numark V7 set up and i love it but i definately want to be comfortable with vinyl. can someone refer me to some inexpensive needles that in their opinion will last? i highly doubt the tables will ever leave my house as i use my v7 set up everywhere but just incase i want to make sure im good to go. Thank you.