Semi-Permanent Hair Straightening

Well I never used to straighten my hair when it was long, but when i cut it to my shoulders it was just so easy to straighten that I started to do it on a regular basis. Now I am trying to grow my hair back out and would like to try having it long and straight but the blowdryer is just not as effective on my hair at this length. I read that The Miano-Viel Salon and Spa in NY has their own secret process that lasts 3-5 months. I am in southern california and am wondering if anyone knows of anything else that lasts something like this time period of under half a year? I dont' want to do something as permanent as TR because i know that after a year or so I will miss my curls just like after a year i missed my long hair. thanks
~M~