What kind of boot's are they? I really depends what kind of boot's they are. i find that Ugg boot's are best with dark or light skinny jeans or even black ones.
i would say to try find a style of skinny jean's that suit you, black one's tend to suit everyone, you can get black skinny jeans for around �20/�25 from new look (called Disco's). - I say this because the best kind of trousers to tuck into boots are skinny jean's because otherwise they can 'bag' around the knee. you could possibly try some bootcut jeans? you can get black bootcut jean's from new look for �10 (called Hula).
i hope this could be of some help to you!