I got my daughter off a bottle and onto a sippy and straw cups by just throwing all her bottles in the trash. She of course cried and would throw her sippy cup at first. But if she was thirsty enough she would use the sippy cup. Now she loves straws, her sippy, and grown up cups. I just continued to encouraged her and offer her the sippy and my husband would drink out of them to show her it was fun. Eventually she tried it out and copied her dad because she's a daddy's girl.
With my Alex I had to "Supernanny" it :D He was using his bottles as a pacifier and drinking too much. I gave him a warning (a few days before and the day before I think), bought him some cute big boy cups and straw cups with favorite characters and one day we just said bye bye to all bottles at once. He resisted a for a day or two, but never got dehydrated, eventually he was really proud to be drinking like a big boy :) Those couple of days were not easy though... He needed lots of encouragement. Best of luck to you :)