Yes, you'll need a frame. Your best best is to buy a complete soft top kit from Bestop (they make the OEM soft tips for Jeep) which will come with the top, frame, and everything you need!
I bought my son a Bestop for his 2002 TJ. Excellent product. It was a little tight to begin with, so much so we (I) broke a zipper trying to put it on but Bestop replaced it with no problems. Now it fits great. Much better than the cheap top it originally came with when I bought the TJ used.
i requested soft top from ebay. it was expensive with shipping to azerbaijan. i wanted to buy top was made in usa. i was in choke when i got soft top. it was made in china. yeah, i used it everywhere in sand and mud and i enjoy it. but i might to buy it for less price direct from china.