substitute for foam roller
There is another alternative to purchasing a foam roller that works quite well: using athletic tape, attach two tennis balls together by wrapping the tape sort of in a "figure-8" shape. I had a persistent case of ITB inflammation for about a year and a half, and this was what my PT recommended for massaging out the band. It works just like the roller does, but it's cheaper and more portable.
Good luck, and be persistent! Sometimes it takes a little patience while waiting for it to heal.